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KIRCHHOFF FORMULA WITH LINE INTEGRAL FORM AND ITS APPLICATIONS
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作者 顾长青 徐金平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期183-187,共5页
In this paper, Kirchhoff formula has been transformed from surface integral form into a line integral form. The new form of the formula can be applied to separate geometrical optical field from diffraction field, and ... In this paper, Kirchhoff formula has been transformed from surface integral form into a line integral form. The new form of the formula can be applied to separate geometrical optical field from diffraction field, and reduce the time of numerical computation greatly. Based on the new form, an analytical formula of diffraction field in the far zone has been presented for the polygonal aperture illuminated by a uniform plane wave. 展开更多
关键词 wave propagation DIFFRACTION integrals of Cauchy type Kirchhoff formula line integral
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Analytic Expression of Meso-Criterion on Dynamic Fracture
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作者 范天佑 李春 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期140+135-139,共6页
This study presents a meso-criterion of dynamic fracture, on the basis of stress in integral form In such way the difficulty due to the singularity of stress distribution at the crack tip is overcome. A micro-paramete... This study presents a meso-criterion of dynamic fracture, on the basis of stress in integral form In such way the difficulty due to the singularity of stress distribution at the crack tip is overcome. A micro-parameter, the atom radius, is introduced into the criterion.Meanwhile a characteristic time concept is taken into account for describing the inertia effect of material. The criterion reveals The criterion reveals the effects of loading rate, defect and sample geometry,material constants including the micro-structure parameter. 展开更多
关键词 dynamic fracture meso-scale/stress in integral form
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New Majorized Results on Hilbert's Integral Inequality
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作者 谢鸿政 吕中学 辛玉梅 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第4期69-75,共7页
In this paper, some new majorized results on Hilbert’s integral inequality are showed.
关键词 Hilbert’s integral inequality
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远程开放教育网络学习平台动力机制刍议
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作者 陈宇翔 李少杰 《福建电脑》 2004年第8期95-96,共2页
本文通过对目前网络学习平台的动力机制进行分析 ,阐述网络学习平台动力机制的创设和实施。议述了网络学习平台必须注重“自主学习、兴趣激励、评价与监控”的教育动力机制及“积分式网络教学管理机制的创设 。
关键词 网络学习平台 动力机制 “积分式” 网络教学管理机制
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A Note on HilbertsIntegral Inequalities 被引量:50
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作者 杨必成 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期83-86, ,共4页
In this note,by introudcing a couple of parameters T,t and estimating the weight function effectively,Hilberts integral inequalities are well generalized. As applications,we give some new Hilbers type inequalities.
关键词 Hilberts integral inequality weight function decreasing function
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Operator Fredholm Integration Equation in Intermediate Coordinate-Momentum Representation and Its Analogue to Thermo Conduction Equation 被引量:2
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作者 FAN Hong-Yi TANG Xu-Bing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1169-1172,共4页
Using the technique of integration within an ordered product (IWOP) of operators we construct intermediate coordinate-momentum representation, with which we build a type of operator Fredholm integration equation tha... Using the technique of integration within an ordered product (IWOP) of operators we construct intermediate coordinate-momentum representation, with which we build a type of operator Fredholm integration equation that is an operator generalization of the solution of thermo conduction equation. Then we seach for the solution of operator Fredholm integration equations, which provides us with a new approach for deriving some operator identities. 展开更多
关键词 operator Fredholm equation intermediate coordinate-momentum representation thermo conduction equation
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Covariant Prolongation Structure of Konno-Asai-Kakuhata Equation 被引量:2
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作者 XIE Tao LI Min-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期565-567,共3页
Based upon the covariant prolongation structures theory, we construct the sl(2, R)×R(p) prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtai... Based upon the covariant prolongation structures theory, we construct the sl(2, R)×R(p) prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtain the inverse scattering equations given by Konno et al. and the corresponding Riccati equation. The Baecklund transformations are also presented. 展开更多
关键词 integrable equation covariant prolongation structure Baecklund transformation
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Exact Traveling Wave Solutions for a Kind of Generalized Ginzburg-Landau Equation 被引量:8
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作者 LIUCheng-Shi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期787-790,共4页
Using a complete discrimination system for polynomials, new exact traveling wave solutions for generalized Ginzburg-Landau equation are obtained. The method has general meaning for many similar problems.
关键词 generalized Ginzburg-Landau equation elementary integral method polynomialcomplete discrimination system
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Debris Flow Formation Process and Critical Hydrodynamic Conditions in the Meizoseismal Area of the Wenchuan Earthquake 被引量:5
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作者 WANG Jun YU Yan +2 位作者 PAN Hua-li QIAO Cheng OU Guo-qiang 《Journal of Mountain Science》 SCIE CSCD 2015年第3期699-710,共12页
Abstract: The Wenchuan earthquake generated strong surface disturbances and triggered a large number of loose deposits, resulting in the disaster- prone environment with special watershed hydrological characteristics... Abstract: The Wenchuan earthquake generated strong surface disturbances and triggered a large number of loose deposits, resulting in the disaster- prone environment with special watershed hydrological characteristics. This paper was to propose a debris flow formation process and explore the permeability characteristics and critical hydrodynamic conditions of the loose deposits triggered by the earthquake. The Guo Juanyan gully (31005'27" N to 31005'46" N, 103036'58" E to 103037'09" E) in Du Jiangyan City, located in the meizoseismal areas of the Wenchuan earthquake, was chosen as the study area and the disaster-prone environment was analyzed. The formation process of the debris flow was first proposed using a stability analysis, and then, the permeability characteristics of loose deposits were determined via in situ permeability experiments. Finally, the critical 1 h rainfall was simulated through a distributed hydrological model and verified by field observations. The formation process of debris flow could be divided into three stages based on the relationship between the hydrodynamic force and loose deposit resistance. The critical 1 h rainfall amounts under three antecedent moisture conditions (I-dry, Ⅱ-normal and Ⅲ-wet) were 52 mm/h, 43 mm/h and 34 mm/h, respectively. This study proposed a debris flow formation process in the meizoseismal areas of the Wenchuan earthquake based on the stability analysis and defined the rainfall threshold for debris flow early warning at the local level, which is significant for debris flow mitigation and risk management. 展开更多
关键词 Wenchuan Earthquake Debris flow Disaster-prone environment Permeabilitycharacteristics Hydrodynamic condition
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Application of Eigenkets of Bosonic Creation Operator in Deriving Some New Formulas of Associated Laguerre Polynomials 被引量:1
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作者 FAN Hong-Yi WANG Tong-Tong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期315-320,共6页
Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we de... Using the resolution of unity composed of bosonic creation operator's eigenkets and annihilation operator's un-normalized eigenket, which is a new quantum mechanical representation in contour integration form, we derive new contour integration expression of associated Laguerre polynomials L^ρm (|z|^2) and its generalized generating function formula. A series of recursive relations regarding to L^ρm (|z|^2) are also deduced in the context of the Fock representation by algebraic method. 展开更多
关键词 bosonic creation operator Laguerre polynomials contour integration
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New Route to Deducing Integration Formulas by Virtue of the IWOP Techniqu~ 被引量:1
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作者 FAN Hong-Yi LI Hong-Qi XU Xing-Lei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期415-417,共3页
We point out a new route to deducing integration formulas, i.e., using the technique of integration within an ordered product (IWOP) of operators we derive some new integration formulas, which seems concise. As a by... We point out a new route to deducing integration formulas, i.e., using the technique of integration within an ordered product (IWOP) of operators we derive some new integration formulas, which seems concise. As a by-product, some new operator identities also appear. 展开更多
关键词 the IWOP technique new integration formulas new operator identities Hermite polynomial
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Operator Methods in High Order Partial Differential Equation 被引量:1
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作者 毕光庆 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期88-101,共14页
For linear partial differential equation 〔 2t 2-a 2P( x)〕 m u=f(x,t), where m1,X∈R n,t∈R 1, the author gives the analytic solution of the initial value problem using the operators sh(tP( x) 1/2 )... For linear partial differential equation 〔 2t 2-a 2P( x)〕 m u=f(x,t), where m1,X∈R n,t∈R 1, the author gives the analytic solution of the initial value problem using the operators sh(tP( x) 1/2 )P( x) 1/2 . By representing the operators with integrals, explicit solutions are obtained with an integral form of a given function. 展开更多
关键词 SH operators parial differential equation infinite order differential operators h k(x τ)function
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3D Modeling and Born approximation inversion for the borehole surface electromagnetic method 被引量:1
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作者 Wang Zhigang He Zhanxiang Wei Wenbo 《Applied Geophysics》 SCIE CSCD 2007年第2期84-88,共5页
We present a 3D approach to numerical modeling of the borehole-surface electromagnetic (BSEM) method. The 3D electromagnetic response created by a vertical line current source in a layered medium is modeled using th... We present a 3D approach to numerical modeling of the borehole-surface electromagnetic (BSEM) method. The 3D electromagnetic response created by a vertical line current source in a layered medium is modeled using the 3D integral equation method. The modeling results are consistent with analytical solutions. 3D Born approximation inversion of BSEM data is also conducted for reservoir delineation. The inversion method is verified by a synthetic reservoir model. 展开更多
关键词 Borehole surface EM technique vertical line source integral equation.
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A NEW SINGULARITY EXTRACTION TECHNIQUE FOR TDEFIE 被引量:1
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作者 Liu Feng Zhou Dongming Cai Mingjuan Ren Meng He 3iangguo 《Journal of Electronics(China)》 2007年第5期686-689,共4页
A new singularity extraction technique is presented to calculate accurately the singular integrals in Time Domain Electric Field Integral Equation (TDEFIE).In singularity extraction pro- cedure,through the aid of the ... A new singularity extraction technique is presented to calculate accurately the singular integrals in Time Domain Electric Field Integral Equation (TDEFIE).In singularity extraction pro- cedure,through the aid of the first order Taylor series of time base function including time-retardation,the singularity of the integrand can be removed.The surface current density and backscattered far-field response of a conducting cube illuminated by a Gaussian plane wave is com- puted using the presented technique.Comparisons are made with the results obtained by the Inverse Discrete Fourier Transform (IDFT) of the frequency domain and the results obtained by using Ve- chinski's time averaging technique,which demonstrate that the presented method with this new time domain singularity extraction technique to solve TDEFIE is very accurate and stable. 展开更多
关键词 Singularity extraction technique Taylor series Time Domain Electric Field Integral Equation (TDEFIE)
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On exponential stability for systems with state delays 被引量:1
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作者 CHEN Yun XUE An-ke +2 位作者 GE Ming WANG Jian-zhong LU Ren-quan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第8期1296-1303,共8页
This paper considers the issue of delay-dependent exponential stability for time-delay systems. Both nominal and uncertain systems are investigated. New sufficient conditions in terms of linear matrix inequalities(LMI... This paper considers the issue of delay-dependent exponential stability for time-delay systems. Both nominal and uncertain systems are investigated. New sufficient conditions in terms of linear matrix inequalities(LMIs) are obtained. These criteria are simple owing to the use of an integral inequality. The model transformation approaches,bounding techniques for cross terms and slack matrices are all avoided in the derivation. Rigorous proof and numerical examples showed that the proposed criteria and those based on introducing slack matrices are equivalent. 展开更多
关键词 Exponential stability Uncertain time-delay systems Integral inequality Slack matrix Linear matrix inequality (LMI)
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European Option Pricing under a Class of Fractional Market 被引量:4
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作者 费为银 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期732-737,共6页
In order to price European contingent claim in a class of fractional Black-Scholes market, where the prices of assets follow a Wick-Ito stochastic differential equation driven by the fractional Brownian motion and mar... In order to price European contingent claim in a class of fractional Black-Scholes market, where the prices of assets follow a Wick-Ito stochastic differential equation driven by the fractional Brownian motion and market coefficients are deterministic functions, the pricing formula of European call option was explicitly derived by the method of the stochastic calculus of tile fractional Brownian motion. A result about fractional Clark derivative was also obtained. 展开更多
关键词 fractional Brownian motion Wick-Ito stochasticintegral fractional It( formula ~ Girsanov thoerem forfractional Brownian motion fractional Clark-Oconetheorem option pricing
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VOICE ACTIVITY DETECTION UNDER RAYLEIGH DISTRIBUTION 被引量:1
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作者 Li Yu Chen Jianming Tan Hongzhou 《Journal of Electronics(China)》 2009年第4期552-556,共5页
This paper presents an improved Voice Activity Detection (VAD) algorithm which uses the Signal-to-Noise Ratio (SNR) measure. We assume that noise Power Spectral Density (PSD) in each spectral bin follows a Rayle... This paper presents an improved Voice Activity Detection (VAD) algorithm which uses the Signal-to-Noise Ratio (SNR) measure. We assume that noise Power Spectral Density (PSD) in each spectral bin follows a Rayleigh distribution. Rayleigh distributions with its asymmetric tail characteristics give a better description of the noise PSD distribution than Gaussian distribution. Under this asstlmption, a new threshold updating expression is derived. Since the analytical integral of the false alarm probability, the threshold updating expression can be represented without the inverse complementary error function and low computational complexity is achieved in our system. Experimental results show that the proposed VAD outperforms or at least is comparable with the VAD scheme presented by Davis under several noise environments and has a lower computational complexity. 展开更多
关键词 Statistical Voice Activity Detection (VAD) Threshold update Rayleigh distribution Computational complexity
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Nested Bethe Ansatz for Spin Ladder Model with Open Boundary Conditions 被引量:2
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作者 WUJun-Fang ZHANGChun-Min +1 位作者 YUERui-Hong LIRun-Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期687-694,共8页
The nested Bethe ansatz (BA) method is applied to find the eigenvalues and the eigenvectors of the transfer matrix for spin-ladder model with open boundary conditions. Based on the reflection equation, we find the gen... The nested Bethe ansatz (BA) method is applied to find the eigenvalues and the eigenvectors of the transfer matrix for spin-ladder model with open boundary conditions. Based on the reflection equation, we find the general diagonal solution, which determines the generalboundary interaction in the Hamiltonian. We introduce the spin-ladder model with open boundary conditions. By finding the solution K± of the reflection equation which determines the nontrivial boundary terms in the Hamiltonian, we diagonalize the transfer matrix of the spin-ladder model with open boundary conditions in the framework of nested BA. 展开更多
关键词 integrable model coordinate bethe ansatz quantum inverse scattering method bethe ansatz equation nested bethe ansatz
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On Quantum Mechanical Hankel Transform and Its Applications
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作者 FAN Hong-Yi WANG Ji-Suo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期304-308,共5页
Based on our preceding works of how to relate the mathematical Hankel transform to quantum mechanical representation transform and how to express the Bessel equation by an operator identity in some appropriate represe... Based on our preceding works of how to relate the mathematical Hankel transform to quantum mechanical representation transform and how to express the Bessel equation by an operator identity in some appropriate representations we propose the concept of quantum mechanical Hankel transform with regard to quantum state vectors. Then we discuss its new applications. 展开更多
关键词 quantum mechanical Hankel transform entangled state integration equation
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Integrating Automatic Patch Snatching System by the Concept of Generalized Mechanisms
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作者 裘建新 林兰天 沈逸平 《Journal of Donghua University(English Edition)》 EI CAS 2008年第2期235-240,共6页
An automatic patch snatching system is described which has three machine cells including dividing equipment, tackling equipment and patch removing equipment. The electromechanical integration design of in-piece tackli... An automatic patch snatching system is described which has three machine cells including dividing equipment, tackling equipment and patch removing equipment. The electromechanical integration design of in-piece tackling system based on the concept of generalized mechanisms is introduced. The design of the dividing equipment, the design of micro-feeding machine equipped with micro-level pressure sensor, and the realizing of computer path for patch snatching are investigated. 展开更多
关键词 PATCH snatching generalized mechanisms electromechanical integration design
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