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From Black Holes to Information Erasure: Uniting Bekenstein’s Bound and Landauer’s Principle
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第8期2185-2194,共10页
This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we ex... This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we explore the implications for black hole thermodynamics, astrophysics, astronomy, information theory, and the search for new laws of nature. The result includes an estimation of the number of bits stored in a black hole (less than 1.4 × 10<sup>30</sup> bits/m<sup>3</sup>), enhancing our understanding of information storage in extreme gravitational environments. This integration offers valuable insights into the fundamental nature of information and energy, impacting scientific advancements in multiple disciplines. 展开更多
关键词 Astrophysics and Astronomy Bekenstein bound Black Hole Thermodynamics Information and Energy Limits Information Theory and Quantum Mechanics Landauer’s Principle
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T-S模糊系统的自触发有限时间H∞控制
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作者 刘晓迪 《计算机测量与控制》 2024年第4期120-128,共9页
为克服事件触发控制对硬件设备的依赖以及控制策略频繁更新的局限,针对一类不确定Takagi-Sugeno(T-S)模糊系统的有限时间H∞控制问题,引入自触发机制,提出一种基于此机制下只与触发时刻状态有关的模糊控制器设计方法;基于自触发机制并... 为克服事件触发控制对硬件设备的依赖以及控制策略频繁更新的局限,针对一类不确定Takagi-Sugeno(T-S)模糊系统的有限时间H∞控制问题,引入自触发机制,提出一种基于此机制下只与触发时刻状态有关的模糊控制器设计方法;基于自触发机制并结合有限时间控制的思想,通过设计触发间隔函数、推导并求解线性矩阵不等式(LMI),使得系统在保障稳定性的前提下,系统运动轨迹不会超过一定的界限,并达到所期望H∞性能水平;同时相较于事件触发机制,自触发机制位于系统内部,无需额外硬件设备接收触发信号且只需利用当前的触发状态信息来预测下一触发时刻,在一定程度上进一步降低系统资源成本;此外,利用李亚普诺夫函数对系统稳定性进行了严格分析,并提供一个确保能够防止芝诺现象发生的证明;最后,通过数值仿真、单连杆刚性机器人系统实例仿真两个实验说明所提方法的有效性。 展开更多
关键词 有限时间有界 自触发控制 鲁棒H∞控制 T-s模糊系统 模糊推理
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最终S-Nekrasov矩阵逆矩阵无穷范数的上界
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作者 蒋建新 《文山学院学报》 2023年第5期95-98,共4页
研究矩阵条件数计算中A的逆矩阵A^(-1)的A|^(-1)|_(∞)的估计问题,利用S-Nekrasov矩阵逆矩阵无穷范数的估计式,结合最终S-Nekrasov矩阵的定义式,得到了该类矩阵的新上界估计式。
关键词 s-Nekrasov矩阵 最终s-Nekrasov矩阵 无穷范数 上界
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THE EQUIVALENT CHARACTERIZATION OF F(p,q,s)SPACE ON BOUNDED SYMMETRIC DOMAINS OF Cn 被引量:4
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作者 黎深莲 张学军 徐思 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1791-1802,共12页
LetΩ be a bounded symmetric domain in Cn. The purpose of this article is to define and characterize the general function space F(p, q, s) on Ω. Characterizing functions in the F(p, q, s) space is a work of consi... LetΩ be a bounded symmetric domain in Cn. The purpose of this article is to define and characterize the general function space F(p, q, s) on Ω. Characterizing functions in the F(p, q, s) space is a work of considerable interest nowadays. In this article, the authors give several equivalent descriptions of the functions in the F(p, q, s) space on Ω in terms of fractional differential operators. At the same time, the authors give the relationship between F(p, q, s) space and Bloch type space on Ω too. 展开更多
关键词 F(p q s space equivalent description bounded symmetric domain
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ON THE LOWER BOUND FOR A CLASS OF HARMONIC FUNCTIONS IN THE HALF SPACE 被引量:4
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作者 张艳慧 邓冠铁 高洁欣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1487-1494,共8页
The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize th... The main objective is to derive a lower bound from an upper one for harmonic functions in the half space, which extends a result of B. Y. Levin from dimension 2 to dimension n 〉 2. To this end, we first generalize the Carleman's formula for harmonic functions in the half plane to higher dimensional half space, and then establish a Nevanlinna's representation for harmonic functions in the half sphere by using HSrmander's theorem. 展开更多
关键词 harmonic function Carleman's formula Nevanlinna's representation for halfsphere lower bound
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Analytical solutions for constant-rate test in bounded confined aquifers with non-Darcian effect 被引量:2
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作者 Yi-jie Zong Li-hua Chen +4 位作者 Jian-jun Liu Yue-hui Liu Yong-xin Xu Fu-wan Gan Liang Xiao 《Journal of Groundwater Science and Engineering》 2022年第4期311-321,共11页
This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical mode... This paper proposes a simplified analytical solution considering non-Darcian and wellbore storage effect to investigate the pumping flow in a confined aquifer with barrier and recharge boundaries.The mathematical modelling for the pumping-induced flow in aquifers with different boundaries is developed by employing image-well theory with the superposition principle,of which the non-Darcian effect is characterized by Izbash’s equation.The solutions are derived by Boltzmann and dimensionless transformations.Then,the non-Darcian effect and wellbore storage are especially investigated according to the proposed solution.The results show that the aquifer boundaries have non-negligible effects on pumping,and ignoring the wellbore storage can lead to an over-estimation of the drawdown in the first 10 minutes of pumping.The higher the degree of non-Darcian,the smaller the drawdown. 展开更多
关键词 Non-Darcian effect bounded aquifer Wellbore storage Izbash’s equation Analytical solution
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What can the changes in shield resistance tell us during the period of shearer's cutting and neighboring shields' advance? 被引量:5
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作者 Cheng Jingyi Wan Zhijun +2 位作者 Peng Syd S. Liu Sifei Ji Yinlin 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第3期361-367,共7页
In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine wer... In order to determine the influence of shearer's cutting and neighboring shields' advance on the support resistance variation, leg pressure data of all 235 shields in the panel LW61 of Cumberland coal mine were analyzed. The results show that the relationship between the leg pressure increment and the distance from shield to front drum of shearer is a quadratic function and that the higher leg pressure increment before shield advance tends to be related to adverse roof conditions. In addition, the three proposed leg pressure increment-related parameters and the three traditional parameters(time-weighted average pressure, setting pressure, and final pressure) of approximately 32000 shield supporting cycles were calculated by a self-developed software package to analyze the correlation between them. The results show that there is a powerful connection between them, and that the three proposed leg pressure increment-related parameters could be used as the indexes to evaluate the interaction between shields and the roof, and to identify the periodic weighting. 展开更多
关键词 Electrohydraulic control shield support Period of shearers cutting and neighboring shields advanceLeg pressure increment shield-roof interaction
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Estimated Bounds for Zeros of Polynomials from Traces of Graeffe Matrices 被引量:1
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作者 Ousmane Moussa Tessa Maimouna Salou Morou Amidou 《Advances in Linear Algebra & Matrix Theory》 2014年第4期210-215,共6页
In this paper, we combine Graeffe matrices with the classical numerical method of Dandelin-Graeffe to estimate bounds for the moduli of the zeros of polynomials. Furthermore, we give some examples showing significant ... In this paper, we combine Graeffe matrices with the classical numerical method of Dandelin-Graeffe to estimate bounds for the moduli of the zeros of polynomials. Furthermore, we give some examples showing significant gain for the convergence towards the polynomials dominant zeros moduli. 展开更多
关键词 Graeffe MATRICEs Numerical Approximation of EIGENVALUEs Dandelin-Graeffe’s Method bounds of ZEROs of POLYNOMIAL
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Bounds for Polynomial’s Roots from Fiedler and Sparse Companion Matrices for Submultiplicative Matrix Norms 被引量:1
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作者 Mamoudou Amadou Bondabou Ousmane Moussa Tessa Amidou Morou 《Advances in Linear Algebra & Matrix Theory》 2021年第1期1-13,共13页
We use submultiplicative companion matrix norms to provide new bounds for roots for a given polynomial <i>P</i>(<i>X</i>) over the field C[<i>X</i>]. From a <i>n</i>... We use submultiplicative companion matrix norms to provide new bounds for roots for a given polynomial <i>P</i>(<i>X</i>) over the field C[<i>X</i>]. From a <i>n</i>×<i>n</i> Fiedler companion matrix <i>C</i>, sparse companion matrices and triangular Hessenberg matrices are introduced. Then, we identify a special triangular Hessenberg matrix <i>L<sub>r</sub></i>, supposed to provide a good estimation of the roots. By application of Gershgorin’s theorems to this special matrix in case of submultiplicative matrix norms, some estimations of bounds for roots are made. The obtained bounds have been compared to known ones from the literature precisely Cauchy’s bounds, Montel’s bounds and Carmichel-Mason’s bounds. According to the starting formel of <i>L<sub>r</sub></i>, we see that the more we have coefficients closed to zero with a norm less than 1, the more the Sparse method is useful. 展开更多
关键词 Fiedler Matrices Polynomial’s Roots bounds for Polynomials Companion Matrices sparse Companion Matrices Hessenberg Matrices submultiplicative Matrix Norm
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ELEMENTARY DENSITY BOUNDS FOR SELF-SIMILAR SETS AND APPLICATION 被引量:1
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作者 Shaoyuan Xu Weiyi Su 《Analysis in Theory and Applications》 2007年第4期334-342,共9页
Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we ... Falconer[1] used the relationship between upper convex density and upper spherical density to obtain elementary density bounds for s-sets at H S-almost all points of the sets. In this paper, following Falconer[1], we first provide a basic method to estimate the lower bounds of these two classes of set densities for the self-similar s-sets satisfying the open set condition (OSC), and then obtain elementary density bounds for such fractals at all of their points. In addition, we apply the main results to the famous classical fractals and get some new density bounds. 展开更多
关键词 self-similar s-set upper convex density upper spherical density Hausdorff measure elementary density bound
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Impulsive stabilization of a class of nonlinear system with bounded gain error
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作者 马铁东 赵飞亚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期103-108,共6页
Considering mechanical limitation or device restriction in practical application, this paper investigates impulsive stabilization of nonlinear systems with impulsive gain error. Compared with the existing impulsive an... Considering mechanical limitation or device restriction in practical application, this paper investigates impulsive stabilization of nonlinear systems with impulsive gain error. Compared with the existing impulsive analytical approaches,the proposed impulsive control method is more practically applicable, which includes control gain error with an acceptable boundary. A sufficient criterion for global exponential stability of an impulsive control system is derived, which relaxes the condition for precise impulsive gain efficiently. The effectiveness of the proposed method is confirmed by theoretical analysis and numerical simulation based on Chua's circuit. 展开更多
关键词 bounded gain error impulsive control exponential stability Chua's circuit
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Six-Dimensional ab initio Potential Energy Surface and Bound States for He-H2S Complex
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作者 Chao-ying Han Ting Jiang +1 位作者 Hua Zhu Hong-jun Fan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第3期319-326,I0002,共9页
We present a new six-dimensional potential energy surface for He-H2S including the intramolecular Q1,Q2,and Q3 normal modes for theν1 symmetric stretching,ν2 bending andν3 asymmetric stretching of H2S.The potential... We present a new six-dimensional potential energy surface for He-H2S including the intramolecular Q1,Q2,and Q3 normal modes for theν1 symmetric stretching,ν2 bending andν3 asymmetric stretching of H2S.The potential was calculated at the coupled-cluster singles and doubles with noniterative inclusion of connected triples[CCSD(T)]-F12a level with augmented correlation-consistent polarized-valence triple-zeta(aug-cc-p VTZ)basis set plus the midpoint bond function(3s3p2d1f1g).Three vibrationally averaged potentials with H2S at the vibrational ground stateν1 as well as the excited statesν2 andν3 were generated from the integration of the six-dimensional potential over the Q1,Q2 and Q3 coordinates.Each potential has a planar T-shaped global minimum,a planar local minimum,two inplane saddle points as well as an out-plane saddle point.The global minimum is located at R=3.46A,θ=109.9° andφ=0.0° with a well depth of 35.301 cm^-1.The radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm were employed to calculate the rovibrational energy levels.The calculated band origins are blue-shifted(0.025 cm^-1 and 0.031 cm^-1)and(0.041 cm^-1 and 0.060 cm^-1)for He-(paraH2S)and He-(ortho-H2S)in theν2 andν3 region of the H2S molecule,respectively. 展开更多
关键词 He-H2s Potential energy surface bound state
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Detection of spin current through a quantum dot with Majorana bound states
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作者 Ning Wang Xingtao An Shuhui Lv 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期127-131,共5页
The spin transport properties are theoretically investigated when a quantum dot(QD)is side-coupled to Majorana bound states(MBSs)driven by a symmetric dipolar spin battery.It is found that MBSs have a great effect on ... The spin transport properties are theoretically investigated when a quantum dot(QD)is side-coupled to Majorana bound states(MBSs)driven by a symmetric dipolar spin battery.It is found that MBSs have a great effect on spin transport properties.The peak-to-valley ratio of the spin current decreases as the coupling strength between the MBS and the QD increases.Moreover,a non-zero charge current with two resonance peaks appears in the system.In the extreme case where the dot-MBS coupling strength is strong enough,the spin current and the charge current are both constants in the non-resonance peak range.When considering the effect of the Zeeman energy,it is interesting that the resonance peak at the higher energy appears one shoulder.And the shoulder turns into a peak when the Zeeman energy is big enough.In addition,the coupling strength between the two MBSs weakens their effects on the currents of the system.These results are helpful for understanding the MBSs signature in the transport spectra. 展开更多
关键词 Majorana bound states quantum dot spin current Green’s function
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Quantum Mechanics of Moving Bound States 被引量:1
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作者 Y. S. Kim 《Journal of Modern Physics》 2022年第2期138-165,共28页
The quantum mechanics of bound states with discrete energy levels is well understood. The quantum mechanics of scattering processes is also well understood. However, the quantum mechanics of moving bound states is sti... The quantum mechanics of bound states with discrete energy levels is well understood. The quantum mechanics of scattering processes is also well understood. However, the quantum mechanics of moving bound states is still debatable. When it is at rest, the space-like separation between the constituent particles is the primary variable. When the bound state moves, this space-like separation picks up the time-like separation. The time-separation is not a measurable variable in the present form of quantum mechanics. The only way to deal with this un-observable variable is to treat it statistically. This leads to rise of the statistical variables such entropy and temperature. Paul A. M. Dirac made efforts to construct bound-state wave functions in Einstein’s Lorentz-covariant world. In 1927, he noted that the c-number time-energy relation should be incorporated in the relativistic world. In 1945, he constructed four-dimensional oscillator wave functions with one time coordinate in addition to the three-dimensional space. In 1949, Dirac introduced the light-cone coordinate system for Lorentz transformations. It is then possible to integrate these contributions made by Dirac to construct the Lorentz-covariant harmonic oscillator wave functions. This oscillator system can explain the proton as a bound state of the quarks when it is at rest, and explain the Feynman’s parton picture when it moves with a speed close to that of light. While the un-measurable time-like separation becomes equal to the space-like separation at this speed, the statistical variables become prominent. The entropy and the temperature of this covariant harmonic oscillator are calculated. It is shown that they rise rapidly as the proton speed approaches that of light. 展开更多
关键词 bound states in Einstein’s World Bohr and Einstein on the Hydrogen Atom Quark-Parton Puzzle Lorentz Group
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Alternative Error Bounds for Some Numerical Quadrature Rules
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作者 LU Jian-fang FENG Ping-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期108-113,共6页
Similar to having done for the mid-point and trapezoid quadrature rules,we obtain alternative estimations of error bounds for the Simpson's quadrature rule involving n-time(1 ≤ n ≤ 4) differentiable mappings and ... Similar to having done for the mid-point and trapezoid quadrature rules,we obtain alternative estimations of error bounds for the Simpson's quadrature rule involving n-time(1 ≤ n ≤ 4) differentiable mappings and then to the estimations of error bounds for the adaptive Simpson's quadrature rule. 展开更多
关键词 n-numerical quadrature rule simpson's quadrature rule adaptive quadrature rule differentiable mapping error bounds
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REMARKS ON BOUNDS ON THE DISCREPANCY OF APPROXIMATE SOLUTIONS CONSTRUCTED BY GODUNOV'S SCHEME
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作者 王靖华 《Acta Mathematica Scientia》 SCIE CSCD 1989年第4期437-452,共16页
The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with sma... The bounds on the discrepancy of approximate solutions constructed by Gedunov's scheme to IVP of isentropic equations of gas dynamics are obtained, Three well-knowu results obtained by Lax for shock waves with small jumps for general quasilinear hyperbolic systems of conservation laws are extended to shock waves for isentropic equations of gas dynamics in a bounded invariant region with ρ=0 as one of boundries of the region. Two counterexamples are given to show that two iuequalities given by Godunov do not hold for all rational numbers γ∈(1, 3]. It seems that the approach by Godunov to obtain the forementioned bounds may not be possible. 展开更多
关键词 TE REMARKs ON bounds ON THE DIsCREPANCY OF APPROXIMATE sOLUTIONs CONsTRUCTED BY GODUNOV’s sCHEME
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Glycosidically Bound Volatile Compounds of Satureja montana L.,S.cuneifolia Ten.,S.subspicata Vis.and Endemic S.visianii SiliC
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作者 Valerija Dunkic Ivana Radovanovic +1 位作者 Nada Bezic Elma Vuko 《Advances in Biological Chemistry》 2015年第7期235-238,共4页
In this paper, the glycoconjugated volatile compounds of four Croatian Satureja species (Satureja montana L., S. cuneifolia Ten., S. subspicata Vis. and endemic S. visianii Silic) were investigated. Content and compos... In this paper, the glycoconjugated volatile compounds of four Croatian Satureja species (Satureja montana L., S. cuneifolia Ten., S. subspicata Vis. and endemic S. visianii Silic) were investigated. Content and composition of these compounds were examined depending on the stage of plant development. GC and GC–MS analysis of volatile aglycones revealed twenty-one compounds. Thymoquinone, geraniol and carvacrol were detected in all vegetative phases of the investigated plants. Other quantitatively important aglycones were eugenol and thymol of S. montana, phenyl ethyl alcohol, benzene acetaldehyde, borneol, α-terpineol, thymol and eugenol of S. cuneifolia, phenyl ethyl alcohol, benzene acet-aldehyde, terpinen-4-ol, α-terpineol and β-ionone of S. subspicata and camphor, thymol and 8a-acetoxylemolol of S. visianii. Moderate similarity in the chemical composition of essential oils and volatile aglycones of investigated plant species indicate that many biologically active compounds are glycosylated and accumulate as non-volatile glycosides. 展开更多
关键词 satureja montana s.cuneifolia s.subspicata s.visianii Glicosydically bound Volatiles Free Aglycones
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S-Sparse Ostrowski-Brauer矩阵线性互补问题的误差界及其应用
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作者 刘毅 高磊 《应用数学》 北大核心 2023年第1期1-15,共15页
本文研究S-Sparse Ostrowski-Brauer (S-SOB)矩阵线性互补问题误差界的估计问题.利用矩阵不等式放缩技术及S-SOB矩阵逆矩阵无穷大范数,获得S-SOB矩阵线性互补问题的误差界,该界仅依赖于S-SOB矩阵的元素.在此基础上,给出S-SOB-B矩阵线性... 本文研究S-Sparse Ostrowski-Brauer (S-SOB)矩阵线性互补问题误差界的估计问题.利用矩阵不等式放缩技术及S-SOB矩阵逆矩阵无穷大范数,获得S-SOB矩阵线性互补问题的误差界,该界仅依赖于S-SOB矩阵的元素.在此基础上,给出S-SOB-B矩阵线性互补问题的误差界,并从理论上证明所给误差界在一定条件下优于García-Esnaola等(2009)和LIU等(2021)所给的结果.最后,通过数值算例进一步阐明了结果的有效性. 展开更多
关键词 线性互补问题 误差界 s-sOB矩阵 s-sOB-B矩阵
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均匀磁场下二维拓扑绝缘体边缘态的多重Andreev反射研究
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作者 杨雪 吕博 《现代电子技术》 北大核心 2024年第4期17-22,共6页
研究均匀磁场下的二维拓扑绝缘体在超导隧道结中的电压偏置约瑟夫森结的输运性质,电流-电压特性显示了马约拉纳束缚态的存在。在亚谐隙结构中,也可以观察到磁场对超导能隙的影响。研究结果表明,在S波超导体/正常金属/S波超导结的隧道谱... 研究均匀磁场下的二维拓扑绝缘体在超导隧道结中的电压偏置约瑟夫森结的输运性质,电流-电压特性显示了马约拉纳束缚态的存在。在亚谐隙结构中,也可以观察到磁场对超导能隙的影响。研究结果表明,在S波超导体/正常金属/S波超导结的隧道谱中存在亚谐隙结构。透明度只影响超导结的零偏压电导值的大小,而不影响亚谐隙结构的位置。但是在磁场作用下,亚谐隙结构会发生变化,不再固定出现在特定位置。这一结果对应于拓扑螺旋态中超导和铁磁序之间的相互作用。 展开更多
关键词 拓扑绝缘体 多重Andreev反射 超导隧道结 约瑟夫森结 亚谐隙结构 马约拉纳束缚态 s波超导体 准粒子波函数
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基于GA-BP的煤矿大型机电设备D-S数据融合故障诊断的研究 被引量:3
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作者 马宪民 梁兰 +1 位作者 张永强 施乐平 《煤炭技术》 CAS 北大核心 2016年第1期218-221,共4页
根据多传感器数据融合理论,研究了煤矿大型机电设备故障类型,提出了用多传感器数据融合技术建立2级机电设备故障诊断的方法。在特征级上采用遗传算法优化BP神经网络(GA-BP),对大量多传感器监测数据进行降维并建立基本信任分配函数;在决... 根据多传感器数据融合理论,研究了煤矿大型机电设备故障类型,提出了用多传感器数据融合技术建立2级机电设备故障诊断的方法。在特征级上采用遗传算法优化BP神经网络(GA-BP),对大量多传感器监测数据进行降维并建立基本信任分配函数;在决策级采用D-S证据理论算法,克服故障诊断过程的不确定性,以提高故障诊断的准确性。 展开更多
关键词 故障诊断 数据融合 GA—BP算法 D—s证据理论 采煤机
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