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Higher-order optimality conditions for multiobjective optimization through a new type of directional derivatives
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作者 HUANG Zheng-gang 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期543-557,共15页
This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this n... This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this notion characterizations of strict local minima of order k for a multiobjective optimization problem with a nonempty set constraint are established,generalizing the corresponding scalar case obtained by Studniarski[3].Also necessary not sufficient and sufficient not necessary optimality conditions for this minima are derived based on our directional derivatives,which are generalizations of some existing scalar results and equivalent to some existing multiobjective ones.Many examples are given to illustrate them there. 展开更多
关键词 strict local minima of order k multiobjective optimization higher-order optimality conditions higher-order directional derivatives
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Relations of 3D directional derivatives and expressions of typical differential operators 被引量:3
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作者 YIN Li LüGui-xia SHEN Long-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第2期221-229,共9页
Relations of the 3D multi-directional derivatives are studied in this paper.These relations are applied to a geeral second-order linear elliptical operator and the corresponding expression are obtained.These relations... Relations of the 3D multi-directional derivatives are studied in this paper.These relations are applied to a geeral second-order linear elliptical operator and the corresponding expression are obtained.These relations and expressions play important roles in the meshless finite point method. 展开更多
关键词 3D directional derivative general elliptical operator
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Extremum of second-order directional derivatives 被引量:1
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作者 LU Gui-xia WU Hao SHEN Long-jun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第4期379-389,共11页
In this paper, the extremum of second-order directional derivatives, i.e. the gradient of first-order derivatives is discussed. Given second-order directional derivatives in three nonparallel directions, or given seco... In this paper, the extremum of second-order directional derivatives, i.e. the gradient of first-order derivatives is discussed. Given second-order directional derivatives in three nonparallel directions, or given second-order directional derivatives and mixed directional derivatives in two nonparallel directions, the formulae for the extremum of second-order directional derivatives are derived, and the directions corresponding to maximum and minimum are perpendicular to each other. 展开更多
关键词 Finite point method second-order directional derivative extremum.
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Image Filter for Removal of Impulse Noise Based on Directional Derivatives 被引量:2
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作者 KONG Tao LI Jun-i CHEN Gang 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期91-102,共12页
One of the most common image processing tasks involves the removal of noise from images.Noise can be introduced during image capture,during transmission,or during storage.For design purposes,noise sources are frequent... One of the most common image processing tasks involves the removal of noise from images.Noise can be introduced during image capture,during transmission,or during storage.For design purposes,noise sources are frequently approximated by random variables with a known probability distribution.One common noise model corrupts a signal by introducing impulses.And the surface of the image disturbed by impulse noise displays many peaks or vales.According to the characteristic of impulse noise,a novel algorithm is proposed to the detection of impulse noise point from images based on directional derivatives.First,the theory of calculus on directional derivatives is introduced in detail.Then it is applied to the field of image to removing noise with the discrete form derived from its continuous mathematical model.And a number of contrasting simulations illustrate that our algorithm not only can preserve the structure information while removing impulse noise but also can mostly save the gray value of the pixels undisturbed by noise.In addition,the comparisons of the filtering performance for removing impulse noise are analyzed in detail in the case of different noise densities,and also show that the algorithm suggested outperforms the conventional filter algorithms such as mean filter,median filter and so on in speed and impulse noise reduction,especially in random-valued impulse noise reduction.So it is a very good alternative to the existing schemes. 展开更多
关键词 level sets directional derivatives impulse noise median filter
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Directional Derivatives of Difference Functions of Nonsmooth Max-functions
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作者 Lu-lin Tan 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第3期495-502,共8页
In this paper, we give an upper estimate for the Clarke-Rockafellar directional derivatives of a function of the form f - g, where f, g are max-functions defined by locally Lipschitz but not necessarily differentiable... In this paper, we give an upper estimate for the Clarke-Rockafellar directional derivatives of a function of the form f - g, where f, g are max-functions defined by locally Lipschitz but not necessarily differentiable functions on a closed convex set in a Euclidean space. As an application, we give a sufficient condition for f - g to have an error bound. 展开更多
关键词 Clarke-rockafellar directional derivatives generalized directional derivatives rademacher theorem dini-directional derivatives max-functions error bound
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Relations between Directional Derivatives for Smooth Functions in 2D and 3D Spaces
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作者 Gui-xia LU Long-jun SHEN 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2016年第4期899-912,共14页
In this paper, relations between directional derivatives are considered for smooth functions both in 2D and 3D spaces. These relations are established in the form of linear combinations of directional derivatives with... In this paper, relations between directional derivatives are considered for smooth functions both in 2D and 3D spaces. These relations are established in the form of linear combinations of directional derivatives with their coefficients having simple form and structural regularity. By them, expressions based on directional derivatives for some typical differential operators are derived. This builds up a solid mathematical foundation for further study on numerical computation by the finite point method based on directional difference. 展开更多
关键词 2D space 3D space directional derivatives finite point method
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Directional Derivative and Subgradient of Cone-Convex Set-Valued Mappings with Applications in Set Optimization Problems
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作者 Yu Han 《Journal of the Operations Research Society of China》 CSCD 2024年第4期1103-1125,共23页
In this paper,we introduce a new directional derivative and subgradient of set-valued mappings by using a nonlinear scalarizing function.We obtain some properties of directional derivative and subgradient for cone-con... In this paper,we introduce a new directional derivative and subgradient of set-valued mappings by using a nonlinear scalarizing function.We obtain some properties of directional derivative and subgradient for cone-convex set-valued mappings.As applications,we present necessary and sufficient optimality conditions for set optimization problems and show that the local weak l-minimal solutions of set optimization problems are the global weak l-minimal solutions of set optimization problems under the assumption that the objective mapping is cone-convex. 展开更多
关键词 Set optimization problem Nonlinear scalarizing function directional derivative SUBGRADIENT
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GÂTEAUX DIRECTIONAL DIFFERENTIABILITY OF THE GENERALIZED METRIC PROJECTION IN BANACH SPACES
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作者 Jinlu LI 《Acta Mathematica Scientia》 2025年第4期1597-1618,共22页
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap... Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC. 展开更多
关键词 uniformly convex and uniformly smooth Banach space the generalized metric projection directional differentiability of the generalized metric projection directional derivative of the generalized metric projection
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FEATURE PRESERVING IMAGE INTERPOLATION BY ADAPTIVE BIDIRECTIONAL FLOW
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作者 Fu Shujun Chen Jingnian 《Journal of Electronics(China)》 2006年第1期154-156,共3页
Most image interpolation algorithms currently used suffer visually to some extent the effects of blurred edges and jagged artifacts in the image. This letter presents an adaptive feature preserving bidirectional flow ... Most image interpolation algorithms currently used suffer visually to some extent the effects of blurred edges and jagged artifacts in the image. This letter presents an adaptive feature preserving bidirectional flow process, where an inverse diffusion is performed to enhance edges along the normal directions to the iso-phote lines (edges), while a normal diffusion is done to remove artifacts ('jaggies') along the tangent directions. In order to preserve image features such as edges, angles and textures, the nonlinear diffusion coefficients are locally adjusted according to the first order and the second order directional derivatives of the image. Experimental results on the Lena image demonstrate that our interpolation algorithm substantially improves the subjective quality of the interpolated images over conventional interpolations. 展开更多
关键词 Anisotropic diffusion Bidirectional flow directional derivatives Edge enhancement Image interpolation Inverse flow
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Importance Analysis of a Multi-state System Based on Direct Partial Logic Derivatives and Multi-valued Decision Diagrams 被引量:1
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作者 古莹奎 李晶 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期789-792,共4页
Importance analysis quantifies the critical degree of individual component. Compared with the traditional binary state system,importance analysis of the multi-state system is more aligned with the practice. Because th... Importance analysis quantifies the critical degree of individual component. Compared with the traditional binary state system,importance analysis of the multi-state system is more aligned with the practice. Because the multi-valued decision diagram( MDD) can reflect the relationship between the components and the system state bilaterally, it was introduced into the reliability calculation of the multi-state system( MSS). The building method,simplified criteria,and path search and probability algorithm of MSS structure function MDD were given,and the reliability of the system was calculated. The computing methods of importance based on MDD and direct partial logic derivatives( DPLD) were presented. The diesel engine fuel supply system was taken as an example to illustrate the proposed method. The results show that not only the probability of the system in each state can be easily obtained,but also the influence degree of each component and its state on the system reliability can be obtained,which is conducive to the condition monitoring and structure optimization of the system. 展开更多
关键词 multi-state system(MSS) importance analysis reliability multi-valued decision diagram(MDD) direct partial logic derivative(DPLD) diesel engine fuel supply system
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BrCo (dmgh)_2Py/Zn Promoted Addition of BrCF_2CF_2CH=CHCH_2X to Alkynes: Direct Synthesis of 4,4,5,5-Tetrafluorocyclopentene Derivatives
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作者 Qiao Sheng HU and Chang Ming HU(Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai, 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期661-664,共4页
BrCF2CF2CH=CHCH2X(x=Cl, OAc, OH) reacted smoothly with alkynes in the presence of BrCo(dmgh)2Py/Zn, giving 4,4,5,5-tetrafluorocyclopentene derivatives in moderate yields.
关键词 CH Zn Promoted Addition of BrCF2CF2CH=CHCH2X to Alkynes CF BrCo Direct Synthesis of 4 4 5 5-Tetrafluorocyclopentene derivatives dmgh Zn Promoted Addition of BrCF2CF2CH
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DIRECT DETERMINATION OF NEODYMIUM AND ERBIUM IN RARE EARTH MIXTURE BY DERIVATIVE SPECTROPHOTOMETRY
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作者 ai Xing WANG Ping QI 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期949-952,共4页
The absorption spectra of 4f electron transitions of the complexes of neodymium and erbium with 8-hydroxyquinoline-5-sulphonic acid in the presence of diethylamine and ethanol have been measured by normal and third-de... The absorption spectra of 4f electron transitions of the complexes of neodymium and erbium with 8-hydroxyquinoline-5-sulphonic acid in the presence of diethylamine and ethanol have been measured by normal and third-derivative spectrophotometry. Their molar absorptivities are 70.7 l.mol^(-1).cm^(-1) for Nd and 62.5 l.mol^(-1).cm^(-1) for Er. They are 7.6 times and 14.9 times greater than those of corresponding chlorides, respectively. Use of the third-derivative spectra both eliminates the interference of Ce(Ⅳ) and increases the sensitivity for Nd and Er. Beer,s Law was obeyed from 0-10 ug/ml of Nd and Er. The method has been applied to the determination of neodymium and erbium in rare earth mixtures. 展开更多
关键词 DEA DIRECT DETERMINATION OF NEODYMIUM AND ERBIUM IN RARE EARTH MIXTURE BY derivative SPECTROPHOTOMETRY
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A Stochastic Configuration Network Modeling Method Based on Improved Hidden Layer Output Matrix and Supervisory Mechanism
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作者 Aijun Yan Jing Wang 《Instrumentation》 2025年第4期25-35,共11页
To improve the generalization performance and prediction accuracy of the stochastic configuration network(SCN)model,a novel SCN modeling method is proposed.First,the first-and second-order directional derivatives of t... To improve the generalization performance and prediction accuracy of the stochastic configuration network(SCN)model,a novel SCN modeling method is proposed.First,the first-and second-order directional derivatives of the hidden layer output matrix are calculated.The key factors extracted from the directional derivatives are linearly added to the original hidden layer output matrix to formulate a new hidden layer output matrix.Second,a spatial angle adaptive supervisory mechanism is established to improve the quality of the parameter configuration of the hidden layer nodes.The experimental results show that the proposed method improves the generalization performance and prediction accuracy.This work is a beneficial exploration of the standard SCN algorithm. 展开更多
关键词 stochastic configuration network directional derivative angle adaptive municipal solid waste incineration flue gas oxygen content
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THE TANGENT CONES ON CONSTRAINT QUALIFICATIONS IN OPTIMIZATION PROBLEMS 被引量:3
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作者 黄龙光 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期843-850,共8页
This article proposes a few tangent cones,which are relative to the constraint qualifications of optimization problems.With the upper and lower directional derivatives of an objective function,the characteristics of c... This article proposes a few tangent cones,which are relative to the constraint qualifications of optimization problems.With the upper and lower directional derivatives of an objective function,the characteristics of cones on the constraint qualifications are presented.The interrelations among the constraint qualifications,a few cones involved, and level sets of upper and lower directional derivatives are derived. 展开更多
关键词 Constraint qualifications upper directional derivatives lower directional derivatives strongly directional differentiable concave functions
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Two-Order Approximate and Large Stepsize Numerical Direction Based on the Quadratic Hypothesis and Fitting Method 被引量:3
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作者 Xiaoli Yin Chunming Li Yuan Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第3期901-909,共9页
Many effective optimization algorithms require partial derivatives of objective functions,while some optimization problems'objective functions have no derivatives.According to former research studies,some search d... Many effective optimization algorithms require partial derivatives of objective functions,while some optimization problems'objective functions have no derivatives.According to former research studies,some search directions are obtained using the quadratic hypothesis of objective functions.Based on derivatives,quadratic function assumptions,and directional derivatives,the computational formulas of numerical first-order partial derivatives,second-order partial derivatives,and numerical second-order mixed partial derivatives were constructed.Based on the coordinate transformation relation,a set of orthogonal vectors in the fixed coordinate system was established according to the optimization direction.A numerical algorithm was proposed,taking the second order approximation direction as an example.A large stepsize numerical algorithm based on coordinate transformation was proposed.Several algorithms were validated by an unconstrained optimization of the two-dimensional Rosenbrock objective function.The numerical second order approximation direction with the numerical mixed partial derivatives showed good results.Its calculated amount is 0.2843%of that of without second-order mixed partial derivative.In the process of rotating the local coordinate system 360°,because the objective function is more complex than the quadratic function,if the numerical direction derivative is used instead of the analytic partial derivative,the optimization direction varies with a range of 103.05°.Because theoretical error is in the numerical negative gradient direction,the calculation with the coordinate transformation is 94.71%less than the calculation without coordinate transformation.If there is no theoretical error in the numerical negative gradient direction or in the large-stepsize numerical optimization algorithm based on the coordinate transformation,the sawtooth phenomenon occurs.When each numerical mixed partial derivative takes more than one point,the optimization results cannot be improved.The numerical direction based on the quadratic hypothesis only requires the objective function to be obtained,but does not require derivability and does not take into account truncation error and rounding error.Thus,the application scopes of many optimization methods are extended. 展开更多
关键词 directional derivative numerical differential optimization method quadratic function hypothesis
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LEARNING RATES OF KERNEL-BASED ROBUST CLASSIFICATION 被引量:1
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作者 Shuhua WANG Baohuai SHENG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1173-1190,共18页
This paper considers a robust kernel regularized classification algorithm with a non-convex loss function which is proposed to alleviate the performance deterioration caused by the outliers.A comparison relationship b... This paper considers a robust kernel regularized classification algorithm with a non-convex loss function which is proposed to alleviate the performance deterioration caused by the outliers.A comparison relationship between the excess misclassification error and the excess generalization error is provided;from this,along with the convex analysis theory,a kind of learning rate is derived.The results show that the performance of the classifier is effected by the outliers,and the extent of impact can be controlled by choosing the homotopy parameters properly. 展开更多
关键词 Support vector machine robust classification quasiconvex loss function learning rate right-sided directional derivative
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A TRUST REGION ALGORITHM VIA BILEVEL LINEAR PROGRAMMING FOR SOLVING THE GENERAL MULTICOMMODITY MINIMAL COST FLOW PROBLEMS
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作者 ZhuDetong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第4期459-473,共15页
This paper proposes a nonmonotonic backtracking trust region algorithm via bilevel linear programming for solving the general multicommodity minimal cost flow problems.Using the duality theory of the linear programmin... This paper proposes a nonmonotonic backtracking trust region algorithm via bilevel linear programming for solving the general multicommodity minimal cost flow problems.Using the duality theory of the linear programming and convex theory,the generalized directional derivative of the general multicommodity minimal cost flow problems is derived.The global convergence and superlinear convergence rate of the proposed algorithm are established under some mild conditions. 展开更多
关键词 duality theory trust region method generalized directional derivative general multicommodity minimal cost flow problems.
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ONLINE REGULARIZED GENERALIZED GRADIENT CLASSIFICATION ALGORITHMS
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作者 Leilei Zhang Baohui Sheng Jianli Wang 《Analysis in Theory and Applications》 2010年第3期278-300,共23页
This paper considers online classification learning algorithms for regularized classification schemes with generalized gradient. A novel capacity independent approach is presented. It verifies the strong convergence o... This paper considers online classification learning algorithms for regularized classification schemes with generalized gradient. A novel capacity independent approach is presented. It verifies the strong convergence of sizes and yields satisfactory convergence rates for polynomially decaying step sizes. Compared with the gradient schemes, this al- gorithm needs only less additional assumptions on the loss function and derives a stronger result with respect to the choice of step sizes and the regularization parameters. 展开更多
关键词 online learning algorithm reproducing kernel Hilbert space generalized gra-dient Clarke's directional derivative learning rate
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On Second-order Sufficient Conditions in Constrained Nonsmooth Optimization
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作者 WANG FENG-LING SONG WEN Li Yong 《Communications in Mathematical Research》 CSCD 2010年第3期203-210,共8页
In this paper, we establish a second-order sufficient condition for constrained optimization problems of a class of so called t-stable functions in terms of the first-order and the second-order Dini type directional d... In this paper, we establish a second-order sufficient condition for constrained optimization problems of a class of so called t-stable functions in terms of the first-order and the second-order Dini type directional derivatives. The result extends the corresponding result of [D. Bednarik and K. Pastor, Math. Program. Ser. A, 113(2008), 283-298] to constrained optimization problems. 展开更多
关键词 second-order optimality condition g-stable function Dini directional derivative isolated minimizer
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Fast Evaluation Algorithm for NURBS Surfaces
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作者 Zhang Xiaopeng Tian Jie Wu Enhua 《Computer Aided Drafting,Design and Manufacturing》 2000年第2期1-9,共9页
Through a precise recursion of B-spline bases and the resursive expression of the derivatives of rational surfaces, this paper presents an efficient algorithm for the calculation of NURBS surfaces and all their direct... Through a precise recursion of B-spline bases and the resursive expression of the derivatives of rational surfaces, this paper presents an efficient algorithm for the calculation of NURBS surfaces and all their directional derivatives. The algorithm requires less storage and proves to be stable. 展开更多
关键词 NURBS B-SPLINE de Boor algorithm directional derivative?
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