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Avoiding the Use of Lagrange Multipliers. II. Constrained Extrema of Functionals and the Evaluation of Constrained Derivatives
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作者 David S. Corti Ricardo Fariello 《Journal of Applied Mathematics and Physics》 2024年第8期2764-2788,共25页
A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented ... A method for determining the extrema of a real-valued and differentiable function for which its dependent variables are subject to constraints and that avoided the use of Lagrange multipliers was previously presented (Corti and Fariello, Op. Res. Forum 2 (2021) 59). The method made use of projection matrices, and a corresponding Gram-Schmidt orthogonalization process, to identify the constrained extrema. Furthermore, information about the second-derivatives of the given function with constraints was generated, from which the nature of the constrained extrema could be determined, again without knowledge of the Lagrange multipliers. Here, the method is extended to the case of functional derivatives with constraints. In addition, constrained first-order and second-order derivatives of the function are generated, in which the derivatives with respect to a given variable are obtained and, concomitantly, the effect of the variations of the remaining chosen set of dependent variables are strictly accounted for. These constrained derivatives are valid not only at the extrema points, and also provide another equivalent route for the determination of the constrained extrema and their nature. 展开更多
关键词 Constrained Extrema functional derivatives Projection Matrices
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Computation of the Schrödinger Equation via the Discrete Derivatives Representation Method: Improvement of Solutions Using Particle Swarm Optimization
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作者 Abdelwahab Zerarka H. Saidi +1 位作者 A. Attaf N. Khelil 《Journal of Modern Physics》 2010年第1期44-47,共4页
We develop the discrete derivatives representation method (DDR) to find the physical structures of the Schr?dinger equation in which the interpolation polynomial of Bernstein has been used. In this paper the particle ... We develop the discrete derivatives representation method (DDR) to find the physical structures of the Schr?dinger equation in which the interpolation polynomial of Bernstein has been used. In this paper the particle swarm optimization (PSO for short) has been suggested as a means to improve qualitatively the solu-tions. This approach is carefully handled and tested with a numerical example. 展开更多
关键词 discrete derivativeS SPECTRA Wave function Particle SWARM
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IMPULSIVE EXPONENTIAL SYNCHRONIZATION OF FRACTIONAL-ORDER COMPLEX DYNAMICAL NETWORKS WITH DERIVATIVE COUPLINGS VIA FEEDBACK CONTROL BASED ON DISCRETE TIME STATE OBSERVATIONS
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作者 Ruihong LI Huaiqin WU Jinde CAO 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期737-754,共18页
This article aims to address the global exponential synchronization problem for fractional-order complex dynamical networks(FCDNs)with derivative couplings and impulse effects via designing an appropriate feedback con... This article aims to address the global exponential synchronization problem for fractional-order complex dynamical networks(FCDNs)with derivative couplings and impulse effects via designing an appropriate feedback control based on discrete time state observations.In contrast to the existing works on integer-order derivative couplings,fractional derivative couplings are introduced into FCDNs.First,a useful lemma with respect to the relationship between the discrete time observations term and a continuous term is developed.Second,by utilizing an inequality technique and auxiliary functions,the rigorous global exponential synchronization analysis is given and synchronization criterions are achieved in terms of linear matrix inequalities(LMIs).Finally,two examples are provided to illustrate the correctness of the obtained results. 展开更多
关键词 Fractional-order complex dynamical networks fractional derivative couplings IMPULSES discrete time state observations
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HIGHER RADIAL DERIVATIVE OF BLOCH TYPE FUNCTIONS 被引量:4
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作者 李波 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期433-445,共13页
In this paper, The integral characterizations of alpha-Bloch (little alpha-Bloch) axe given in terms of higher radial derivative, and their characterizations of Caxleson type measure are obtained.
关键词 Bloch type function higher radial derivative Carleson type measure
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Integral Inequalities of Hermite-Hadamard Type for Functions Whose 3rd Derivatives Are <i>s</i>-Convex 被引量:4
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作者 Ling Chun Feng Qi 《Applied Mathematics》 2012年第11期1680-1685,共6页
In the paper, the authors find some new inequalities of Hermite-Hadamard type for functions whose third derivatives are s-convex and apply these inequalities to discover inequalities for special means.
关键词 INTEGRAL INEQUALITY Hermite-Hadamard’s INTEGRAL INEQUALITY s-Convex function derivative Mean
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Development of an improved three-dimensional rough discrete fracture network model:Method and application
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作者 Peitao Wang Chi Ma +3 位作者 Bo Zhang Qi Gou Wenhui Tan Meifeng Cai 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第12期1469-1485,共17页
Structure plane is one of the important factors affecting the stability and failure mode of rock mass engineering.Rock mass structure characterization is the basic work of rock mechanics research and the important con... Structure plane is one of the important factors affecting the stability and failure mode of rock mass engineering.Rock mass structure characterization is the basic work of rock mechanics research and the important content of numerical simulation.A new 3-dimensional rough discrete fracture network(RDFN3D)model and its modeling method based on the Weierstrass-Mandelbrot(W-M)function were presented in this paper.The RDFN3D model,which improves and unifies the modelling methods for the complex structural planes,has been realized.The influence of fractal dimension,amplitude,and surface precision on the modeling parameters of RDFN3D was discussed.The reasonable W-M parameters suitable for the roughness coefficient of JRC were proposed,and the relationship between the mathematical model and the joint characterization was established.The RDFN3D together with the smooth 3-dimensional discrete fracture network(DFN3D)models were successfully exported to the drawing exchange format,which will provide a wide application in numerous numerical simulation codes including both the continuous and discontinuous methods.The numerical models were discussed using the COMSOL Multiphysics code and the 3-dimensional particle flow code,respectively.The reliability of the RDFN3D model was preliminarily discussed and analyzed.The roughness and spatial connectivity of the fracture networks have a dominant effect on the fluid flow patterns.The research results can provide a new geological model and analysis model for numerical simulation and engineering analysis of jointed rock mass. 展开更多
关键词 Jointed rock mass discrete fracture network ROUGHNESS Weierstrass-Mandelbrot function 3D modeling Rock mechanics
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Stabilization of discrete nonlinear systems based on control Lyapunov functions 被引量:1
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作者 Cai Xiushan Wang Xiaodong Lü Ganyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期131-133,共3页
The stabilization of discrete nonlinear systems is studied. Based on control Lyapunov functions, a sufficient and necessary condition for a quadratic function to be a control Lyapunov function is given. From this cond... The stabilization of discrete nonlinear systems is studied. Based on control Lyapunov functions, a sufficient and necessary condition for a quadratic function to be a control Lyapunov function is given. From this condition, a continuous state feedback law is constructed explicitly. It can globally asymptotically stabilize the equilibrium of the closed-loop system. A simulation example shows the effectiveness of the proposed method. 展开更多
关键词 control Lyapunov functions discrete systems STABILIZATION
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High-Order Radial Derivatives of Harmonic Function and Gravity Anomaly 被引量:8
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作者 Ziqing Wei 《Journal of Physical Science and Application》 2014年第7期454-467,共14页
The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation ... The first through ninth radial derivatives of a harmonic function and gravity anomaly are derived in this paper. These derivatives can be used in the analytical continuation application. For the downward continuation of gravity anomaly, the Taylor series approach developed in the paper is equivalent theoretically to but more efficient and storage-saving computationally than the well-known gradient operator approach. Numerical simulation shows that Taylor series expansion constructed by the derived formulas for the radial derivatives of gravity disturbance is still convergent for height up to 4 km. 展开更多
关键词 Harmonic function gravity anomaly gravity disturbance high-order radial derivative analytical continuation.
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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations functionAL variational problems derivatives of higher orders undetermined boundary
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A New Definition for Generalized First Derivative of Nonsmooth Functions 被引量:1
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作者 Ali Vahidian Kamyad Mohammad Hadi Noori Skandari Hamid Reza Erfanian 《Applied Mathematics》 2011年第10期1252-1257,共6页
In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are ap... In this paper, we define a functional optimization problem corresponding to smooth functions which its optimal solution is first derivative of these functions in a domain. These functional optimization problems are applied for non-smooth functions which by solving these problems we obtain a kind of generalized first derivatives. For this purpose, a linear programming problem corresponding functional optimization problem is obtained which their optimal solutions give the approximate generalized first derivative. We show the efficiency of our approach by obtaining derivative and generalized derivative of some smooth and nonsmooth functions respectively in some illustrative examples. 展开更多
关键词 Generalized derivative SMOOTH and NONSMOOTH functionS FOURIER analysis Linear PROGRAMMING functional Optimization
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Dynamics of a Discrete Predator-Prey System with Beddington-DeAngelis Function Response 被引量:1
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作者 Qibin Fang Xiaoping Li Meiyu Cao 《Applied Mathematics》 2012年第4期389-394,共6页
This paper discusses the dynamic behaviors of a discrete predator-prey system with Beddington-DeAngelis function response. We first show that under some suitable assumption, the system is permanent. Furthermore, by co... This paper discusses the dynamic behaviors of a discrete predator-prey system with Beddington-DeAngelis function response. We first show that under some suitable assumption, the system is permanent. Furthermore, by constructing a suitable Lyapunov function, a sufficient condition which guarantee the global attractivity of positive solutions of the system is 展开更多
关键词 discrete BEDDINGTON-DEANGELIS functional RESPONSE PERMANENCE Global ATTRACTIVITY
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Periodic Solutions for a Class of Neutral Functional Differential Equations with Distributed and Discrete Delays 被引量:1
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作者 周宗福 曾力 +1 位作者 贾宝瑞 徐建中 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期485-494,共10页
Based on Krasnoselskii's fixed point theorem,matrix measure and functional analysis methods,some new sufficient conditions for the existence of periodic solutions of neutral functional differential equations with ... Based on Krasnoselskii's fixed point theorem,matrix measure and functional analysis methods,some new sufficient conditions for the existence of periodic solutions of neutral functional differential equations with distributed and discrete delays are obtained. Moreover,we construct an example to illustrate the feasibility of our results. 展开更多
关键词 neutral functional differential equation infinite distributed delay discrete delays Krasnoselskii’s fixed point theorem periodic solutions
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Some Inequalities of Hermite-Hadamard Type for Functions Whose 3rd Derivatives Are <i>P</i>-Convex 被引量:1
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作者 Boyan Xi Shuhong Wang Feng Qi 《Applied Mathematics》 2012年第12期1898-1902,共5页
In the paper, the authors establish some new Hermite-Hadamard type inequalities for functions whose 3rd derivatives are P-convex.
关键词 INTEGRAL INEQUALITY Hermite-Hadamard’s INTEGRAL INEQUALITY P-Convex function derivative
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The Normal Meromorphic Functions Family Concerning Higher Order Derivative and Shared Set by One-Way 被引量:1
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作者 Yi Li 《Advances in Pure Mathematics》 2011年第6期322-324,共3页
Let F be a meromorphic functions family on the unit disc Δ, If for every (the zeros of f is a multiplicity of at least k) and if then and ( ), then F is normal on Δ.
关键词 MEROMORPHIC function NORMALITY Criterion SHARED Set by One-Way Higher Order derivative
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The Higher Derivatives of Bianalytic Functions 被引量:1
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作者 谢春平 刘涛 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期59-62, ,共4页
By using the Cauchy integral formula of bianalytic functions, the formula of higher derivatives of bianalytic functions and Weierstrass Theorem are obtained.
关键词 bianalytic function higher derivative Weierstrass Theorem
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Techniques of Discrete Function Transfers into Continuous Function in Practice 被引量:1
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作者 Ming-Jong Lin 《Engineering(科研)》 2018年第10期680-687,共8页
One confusing question over a long period of time is how transfer the discrete function transfers into continuous function. Recently the issue has been resolved but some details of the transformation process will be i... One confusing question over a long period of time is how transfer the discrete function transfers into continuous function. Recently the issue has been resolved but some details of the transformation process will be introduced in the paper. The correlation coefficients of 100,000 values are established from the two groups of data with the range between -1 and 1, creating a histogram from these correlation coefficient values known as “the probability mass function.” The coefficient values are brought into the discrete distribution function, so that transfers into the discrete cumulative function, next converted into a continuous cumulative function, next which is differentiated to get the density function, so that it is easy to being research analysis. A model will be established during the process of the conversion what the medium is “the least squares algorithm.” Finally, when the integral of the area within the range of the density function equals to 1, this implies that the transformation complete succeeds from the discrete function to the continuous function. 展开更多
关键词 PROBABILITY MASS function discrete CUMULATIVE function Continuous CUMULATIVE function PROBABILITY Density function The Least SQUARES Algorithm
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HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION FUNCTIONS AND THEIR LOGICAL DERIVATIVES 被引量:1
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作者 Sha Zhen Chen Gang Zhejiang University,China 《Analysis in Theory and Applications》 1993年第4期73-88,共16页
In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their... In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their logical derivatives of order α. 展开更多
关键词 HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION functionS AND THEIR LOGICAL derivativeS der HAAR FIF
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SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS 被引量:1
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作者 T.F.Xie S.P.Zhou 《Analysis in Theory and Applications》 1994年第4期100-109,共10页
This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of... This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of deereeon the nodes X_nUY_n(see the definition of the next). 展开更多
关键词 SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE function AND ITS derivativeS BY LAGRANGE INTERPOLATING POLYNOMIALS APPI ZR
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ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF FUNCTIONS AND THEIR DERIVATIVES BY HERMITE INTERPOLATION 被引量:1
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作者 Tingfan Xie Ziyu Wang China Institute of Metrology, China Henan University, China 《Analysis in Theory and Applications》 1994年第3期45-55,共11页
The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen-... The object of this paper is to establish the pointwise estimations of approximation of functions in C^1 and their derivatives by Hermite interpolation polynomials. The given orders have been proved to be exact in gen- eral. 展开更多
关键词 MATH ON THE POINTWISE ESTIMATIONS OF APPROXIMATION OF functionS AND THEIR derivativeS BY HERMITE INTERPOLATION 石瓦
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The derivative-dependent functional variable separation for the evolution equations 被引量:3
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作者 张顺利 楼森岳 屈长征 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2765-2776,共12页
This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which adm... This paper studies variable separation of the evolution equations via the generalized conditional symmetry. To illustrate, we classify the extended nonlinear wave equation utt = A(u, ux)uxx+B(u, ux, ut) which admits the derivative- dependent functional separable solutions (DDFSSs). We also extend the concept of the DDFSS to cover other variable separation approaches. 展开更多
关键词 derivative-dependent functional variable separation evolution equations generalized conditional symmetry
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