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Solution of scattering from rough surface with a 2D target above it by a hybrid method based on the reciprocity theorem and the forward-backward method 被引量:4
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作者 王运华 张彦敏 +1 位作者 贺明霞 郭立新 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第10期3696-3703,共8页
This paper proposes a hybrid method based on the forward-backward method (FBM) and the reciprocity theorem (RT) for evaluating the scattering field from dielectric rough surface with a 2D target above it. Here, th... This paper proposes a hybrid method based on the forward-backward method (FBM) and the reciprocity theorem (RT) for evaluating the scattering field from dielectric rough surface with a 2D target above it. Here, the equivalent electric/magnetic current densities on the rough surface as well as the scattering field from it are numerically calculated by FBM, and the scattered field from the isolated target is obtained utilizing the method of moments (MOM). Meanwhile, the rescattered coupling interactions between the target and the surface are evaluated employing the combination of FBM and RT. Our hybrid method is first validated by available MOM results. Then, the functional dependences of bistatic and monostatic scattering from the target above rough surface upon the target altitude, incident and scattering angles are numerically simulated and discussed. This study presents a numerical description for the scattering mechanism associated with rescattered coupling interactions between a target and an underlying randomly rough surface. 展开更多
关键词 forward-backward method reciprocity theorem 2d target rough surface SCATTERING
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Uncertainty Theory Based Novel Multi-Objective Optimization Technique Using Embedding Theorem with Application to R &D Project Portfolio Selection 被引量:2
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作者 Rupak Bhattacharyya Amitava Chatterjee Samarjit Kar 《Applied Mathematics》 2010年第3期189-199,共11页
This paper introduces a novice solution methodology for multi-objective optimization problems having the coefficients in the form of uncertain variables. The embedding theorem, which establishes that the set of uncert... This paper introduces a novice solution methodology for multi-objective optimization problems having the coefficients in the form of uncertain variables. The embedding theorem, which establishes that the set of uncertain variables can be embedded into the Banach space C[0, 1] × C[0, 1] isometrically and isomorphically, is developed. Based on this embedding theorem, each objective with uncertain coefficients can be transformed into two objectives with crisp coefficients. The solution of the original m-objectives optimization problem with uncertain coefficients will be obtained by solving the corresponding 2 m-objectives crisp optimization problem. The R & D project portfolio decision deals with future events and opportunities, much of the information required to make portfolio decisions is uncertain. Here parameters like outcome, risk, and cost are considered as uncertain variables and an uncertain bi-objective optimization problem with some useful constraints is developed. The corresponding crisp tetra-objective optimization model is then developed by embedding theorem. The feasibility and effectiveness of the proposed method is verified by a real case study with the consideration that the uncertain variables are triangular in nature. 展开更多
关键词 Uncertainty Theory UNCERTAIN Variable EMBEddING theorem α-Optimistic and α-Pessimistic Value R & d Project PORTFOLIO Selection
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On 2-D Cayley-Hamilton Theorem
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作者 郑兵 王国荣 《Journal of Shanghai University(English Edition)》 CAS 2003年第3期214-217,共4页
A new proof of the row Cayley-Hamilton theorem for 2-D system was given in this note. In a similar way, the Column Cay- ley-Hamilton theorem was also presented and proved.
关键词 2-d system Leverrier's relation Cayley-Hamilton theorem.
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure Shell theorem 3d Computer Model Quantum
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3d Model Schrödinger Equation RMS KLEIN GORdON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field density Phase Flow Attraction REPULSION Shell theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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一般模型2-D系统的观测器设计理论 被引量:4
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作者 邹云 孙建中 杨成梧 《自动化学报》 CSCD 北大核心 1994年第4期385-393,共9页
该文讨论了2-D一般模型(2DGM)在标准边界条件下的渐近观测器的存在性条件及其设计问题.为此,首先将由Bisiacco等人在1985年发展起来的相应于对角边界条件的2-D渐近稳定性理论推广到了具有标准边界条件的2-... 该文讨论了2-D一般模型(2DGM)在标准边界条件下的渐近观测器的存在性条件及其设计问题.为此,首先将由Bisiacco等人在1985年发展起来的相应于对角边界条件的2-D渐近稳定性理论推广到了具有标准边界条件的2-D一般模型.在此基础上,借助于局部能控性概念,建立了一系列十分类似于1-D情形的观测器的存在条件,从这些存在条件出发也可以得到相应的观测器设计算法,最后还得出了2DGM的分离性定理. 展开更多
关键词 2-d系统 预测器 模型
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(F,α,ρ,d)-凸性下的非光滑多目标分式规划问题的对偶 被引量:4
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作者 姚元金 《湖北民族学院学报(自然科学版)》 CAS 2014年第2期124-127,共4页
在(F,α,ρ,d)-凸性条件下,研究了一类非光滑多目标分式规划问题的对偶问题,给出并证明了该对偶问题的弱对偶定理,强对偶定理和严格逆对偶定理.所得结论改进和推广了相关的结果.
关键词 (F α ρ d)-凸 非光滑多目标分式规划 弱对偶定理 强对偶定理 严格逆对偶定理
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一类Meyer-konig-Zeller型概率算子逼近的逆定理
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作者 刘生贵 《兰州理工大学学报》 CAS 北大核心 2010年第3期158-161,共4页
用概率分布可以定义概率算子,对于一类Meyer-knig-Zeller型概率算子,利用"插补空间法"研究它的逼近性质,得到该算子逼近的逆定理,对逼近度给出更加精细的刻画.
关键词 Meyer-knig-Zeller型概率算子 逼近 逆定理
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带B-D功能反应函数的捕食者-食饵扩散模型行波解的存在性 被引量:1
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作者 石月莲 薛亚奎 《太原师范学院学报(自然科学版)》 2009年第2期1-5,共5页
文章利用打靶法和不变流形定理研究了带Beddington-DeAngelis功能反应函数的捕食者-食饵扩散模型其行波解的存在性.
关键词 B-d功能反应函数 打靶法 不变流形定理
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D-稳定性区域的单连通性与多项式族的D-稳定性(英文)
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作者 段广仁 《黑龙江大学自然科学学报》 CAS 2001年第1期24-30,共7页
证明了其根位于复平面中某开域的所有n阶多项式的全体构成多项式参数空间中的一个单连通集,并基于这一结果进一步提出了关于一般多面体多项式族D-稳定性的棱边定理和关于一般多项式紧集D-稳定性的边界定理.所得结果包含了多项式... 证明了其根位于复平面中某开域的所有n阶多项式的全体构成多项式参数空间中的一个单连通集,并基于这一结果进一步提出了关于一般多面体多项式族D-稳定性的棱边定理和关于一般多项式紧集D-稳定性的边界定理.所得结果包含了多项式参数无关和相关两种情形.不同于已有结果,作者提出的棱边定理和边界定理不要求多项式集的凸性与单连通性.另外,关于相关参数的多项式集的边界定理还突破了现有结果中关于参数相关关系为仿射映射的限制. 展开更多
关键词 多项式族 相关参数 边界定理 棱边定理 d-稳定性区域 单连通性 凸性 仿射映射
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RSA加密的e、d确定 被引量:2
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作者 江速勇 《福建商业高等专科学校学报》 2007年第1期88-89,107,共3页
RSA算法是一种公钥密码算法,实现RSA算法包括生成RSA密钥,加密和解密数据。利用中国剩余定理提高解密的速度,查看解密时的时钟周期数来确定e和d值。
关键词 RSA算法 中国剩余定理CRT 公开密钥e 私人密钥d CPU时钟周期数
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基于警报信号和D-S证据理论的风电机组故障诊断 被引量:14
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作者 叶春霖 邱颖宁 冯延晖 《太阳能学报》 EI CAS CSCD 北大核心 2019年第12期3613-3620,共8页
数据采集与监视控制系统(SCADA)储存了风电机组大量的警报信号,这些警报信号对故障类型具有一定的指示作用。为了及时有效地检测出风电机组故障,提出一种基于低频SCADA警报信号和D-S证据理论的风电机组故障诊断方法。首先从维修记录中... 数据采集与监视控制系统(SCADA)储存了风电机组大量的警报信号,这些警报信号对故障类型具有一定的指示作用。为了及时有效地检测出风电机组故障,提出一种基于低频SCADA警报信号和D-S证据理论的风电机组故障诊断方法。首先从维修记录中提取故障类型构建辨识框架,然后选取故障当天触发的所有警报信号作为证据源,最后基于改进的D-S理论进行信息融合实现故障诊断。验证结果表明,该方法可以实现风电机组故障的有效诊断,为风电机组故障诊断提供了一种新的思路。 展开更多
关键词 风电机组 SCAdA警报信号 d-S证据理论 贝叶斯定理 故障诊断
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APPROXIMATION BY GENERALIZED MKZ-OPERATORS IN POLYNOMIAL WEIGHTED SPACES 被引量:1
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作者 Lucyna Rempulska Mariola Skorupka 《Analysis in Theory and Applications》 2007年第1期64-75,共12页
We prove some approximation properties of generalized Meyer-Konig and Zeller operators for differentiable functions in polynomial weighted spaces. The results extend some results proved in [1-3,7-16].
关键词 Meyer-konig and Zeller operator polynomial weighted space approximation theorem
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时滞2-D中立型离散状态模型正解的存在性
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作者 刘树堂 邓飞其 刘永清 《控制理论与应用》 EI CAS CSCD 北大核心 2002年第6期851-854,共4页
在Bandch空间中利用不动点定理研究了时滞 2 D二阶中立型离散时间状态模型正解的存在性 .
关键词 存在性 控制理论 时滞2-d中立型离散状态模型 不动点定理 正解
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基于BCD工艺的低噪声振荡器的设计
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作者 周媛媛 解光军 《电子器件》 CAS 2010年第1期41-44,共4页
基于PWM技术的D类音频功放已广泛应用于各类电子产品中,PWM载波由振荡器产生,振荡器的性能直接影响D类功放的性能。文中主要从提高电路抗噪能力的角度提出一种基于BCD工艺的低噪声频率稳定振荡器的设计,噪声电流仅为0.42nA。该电路能在1... 基于PWM技术的D类音频功放已广泛应用于各类电子产品中,PWM载波由振荡器产生,振荡器的性能直接影响D类功放的性能。文中主要从提高电路抗噪能力的角度提出一种基于BCD工艺的低噪声频率稳定振荡器的设计,噪声电流仅为0.42nA。该电路能在10~36V和-40~150℃范围内正常工作,振荡频率随电压的变化率小于1%,且具有主-从工作模式的同步功能。通过一个外接电阻调节振荡频率范围为300~500kHz。该电路已成功应用于一种中功率D类音频功放中。 展开更多
关键词 振荡器 低噪声BCd工艺 采样定理 频率稳定 d类功放
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同平面定轴杆的碰撞与Konig’s定理的推广
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作者 马力 《物理实验》 2008年第5期42-43,46,共3页
Konig’s定理常应用于质点系的动能问题,如果确定了不同方向的等效质量和恢复系数,那么Konig’s定理同样也可以用于描述刚体系统动能.本文从球杆碰撞着手,讨论了Konig’s定理推广的可行性,以及在有摩擦刚体系统问题上的应用前景.
关键词 konig’s定理 等效质量 恢复系数 碰撞 刚体
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Design of twodimensional digital filters using neural networks 被引量:1
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作者 Wang Xiaohua He Yigang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期767-771,共5页
A new approach for the design of two-dimensional (2-D) linear phase FIR digital filters based on a new neural networks algorithm (NNA) is provided. A compact expression for the transfer function of a 2-D linear ph... A new approach for the design of two-dimensional (2-D) linear phase FIR digital filters based on a new neural networks algorithm (NNA) is provided. A compact expression for the transfer function of a 2-D linear phase FIR filter is derived based on its frequency response characteristic, and the NNA, based on minimizing the square-error in the frequency-domain, is established according to the compact expression. To illustrate the stability of the NNA, the convergence theorem is presented and proved. Design examples are also given, and the results show that the ripple is considerably small in passband and stopband, and the NNA-based method is of powerful stability and requires quite little amount of computations. 展开更多
关键词 2-d linear-phase FIR digital filters neural network convergence theorem stability.
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D~*-度量空间中广义F-压缩条件下的不动点定理 被引量:1
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作者 张学智 薛西锋 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2019年第2期232-237,共6页
在完备D~*-度量空间的框架下,首次提出F-压缩映射和广义F-压缩映射的概念,然后使用不同的方法分别在这2种压缩条件下对自映射的不动点的存在性和唯一性进行研究并给出几个新的不动点定理,所得结果在很大程度上改变了已有文献的相关结果.
关键词 F-压缩映射 广义F-压缩映射 d*-度量空间 不动点定理
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D~*-度量空间中次相容映象对的公共不动点定理 被引量:1
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作者 陶陶 薛西锋 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第1期1-5,共5页
基于D^*-度量空间,首次引入次相容映象对和次序列连续映象对的概念,在去掉空间完备性的基础上证明了4个次相容且相对连续自映象的公共不动点问题.所得结果丰富了D^*-度量空间的公共不动点理论.
关键词 d^-度量空间 次相容 相对连续 次序列连续 公共不动点定理
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Central limit theolrem for linear processes generated byⅡD random variables under the sub-linear expectation
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作者 LIU Wei ZHANG Yong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期243-255,共13页
In this paper,we investigate the central limit theorem and the invariance principle for linear processes generated by a new notion of independently and identically distributed(IID)random variables for sub-linear expec... In this paper,we investigate the central limit theorem and the invariance principle for linear processes generated by a new notion of independently and identically distributed(IID)random variables for sub-linear expectations initiated by Peng[19].It turns out that these theorems are natural and fairly neat extensions of the classical Kolmogorov's central limit theorem and invariance principle to the case where probability measures are no longer additive. 展开更多
关键词 central limit theorem invariance principle d random variables sub-linear expectation linear process
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