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AModified Search and Rescue Optimization Based Node Localization Technique inWSN 被引量:1
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作者 Suma Sira Jacob K.Muthumayil +4 位作者 M.Kavitha Lijo Jacob Varghese M.Ilayaraja Irina V.Pustokhina Denis A.Pustokhin 《Computers, Materials & Continua》 SCIE EI 2022年第1期1229-1245,共17页
Wireless sensor network(WSN)is an emerging technology which find useful in several application areas such as healthcare,environmentalmonitoring,border surveillance,etc.Several issues that exist in the designing of WSN... Wireless sensor network(WSN)is an emerging technology which find useful in several application areas such as healthcare,environmentalmonitoring,border surveillance,etc.Several issues that exist in the designing of WSN are node localization,coverage,energy efficiency,security,and so on.In spite of the issues,node localization is considered an important issue,which intends to calculate the coordinate points of unknown nodes with the assistance of anchors.The efficiency of the WSN can be considerably influenced by the node localization accuracy.Therefore,this paper presents a modified search and rescue optimization based node localization technique(MSRONLT)forWSN.The major aim of theMSRO-NLT technique is to determine the positioning of the unknown nodes in theWSN.Since the traditional search and rescue optimization(SRO)algorithm suffers from the local optima problemwith an increase in number of iterations,MSRO algorithm is developed by the incorporation of chaotic maps to improvise the diversity of the technique.The application of the concept of chaotic map to the characteristics of the traditional SRO algorithm helps to achieve better exploration ability of the MSRO algorithm.In order to validate the effective node localization performance of the MSRO-NLT algorithm,a set of simulations were performed to highlight the supremacy of the presented model.A detailed comparative results analysis showcased the betterment of the MSRO-NLT technique over the other compared methods in terms of different measures. 展开更多
关键词 Node localization WSN chaotic map search and rescue optimization algorithm localization error
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LOCAL ERROR ESTIMATES FOR METHODS OF CHARACTERISTICS INCORPORATING STREAMLINE DIFFUSION
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作者 岳兴业 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期564-576,共13页
Allen and Liu (1995) introduced a new method for a time-dependent convection dominated diffusion problem, which combines the modified method of characteristics and method of streamline diffusion. But they ignored the ... Allen and Liu (1995) introduced a new method for a time-dependent convection dominated diffusion problem, which combines the modified method of characteristics and method of streamline diffusion. But they ignored the fact that the accuracy of time discretization decays at half an order when the characteristic line goes out of the domain. In present paper, the author shows that, as a remedy, a simple lumped scheme yields a full accuracy approximation. Forthermore, some local error bounds independent of the small viscosity axe derived for this scheme outside the boundary layers. 展开更多
关键词 convection dominated method of characteristics streamline diffusion local error estimates
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SEMIPARAMETRIC REGRESSION MODELS WITH LOCALLY GENERALIZED GAUSSIAN ERROR'S STRUCTURE
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作者 胡舒合 《Acta Mathematica Scientia》 SCIE CSCD 1998年第S1期68-77,共10页
This paper proposes parametric component and nonparametric component estimators in a semiparametric regression models based on least squares and weight function's method, their strong consistency and rib mean cons... This paper proposes parametric component and nonparametric component estimators in a semiparametric regression models based on least squares and weight function's method, their strong consistency and rib mean consistency are obtained under a locally generallied Gaussinan error's structure. Finally, the author showes that the usual weight functions based on nearest neighbor method satisfy the deigned assumptions imposed. 展开更多
关键词 Semiparametric regression locally generalized Garussian error Strong consistency Rib mean consistency
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Stable Computer Method for Solving Initial Value Problems with Engineering Applications
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作者 Mudassir Shams Nasreen Kausar +1 位作者 Ebru Ozbilge Alper Bulut 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2617-2633,共17页
Engineering and applied mathematics disciplines that involve differential equations in general,and initial value problems in particular,include classical mechanics,thermodynamics,electromagnetism,and the general theor... Engineering and applied mathematics disciplines that involve differential equations in general,and initial value problems in particular,include classical mechanics,thermodynamics,electromagnetism,and the general theory of relativity.A reliable,stable,efficient,and consistent numerical scheme is frequently required for modelling and simulation of a wide range of real-world problems using differential equations.In this study,the tangent slope is assumed to be the contra-harmonic mean,in which the arithmetic mean is used as a correction instead of Euler’s method to improve the efficiency of the improved Euler’s technique for solving ordinary differential equations with initial conditions.The stability,consistency,and efficiency of the system were evaluated,and the conclusions were supported by the presentation of numerical test applications in engineering.According to the stability analysis,the proposed method has a wider stability region than other well-known methods that are currently used in the literature for solving initial-value problems.To validate the rate convergence of the numerical technique,a few initial value problems of both scalar and vector valued types were examined.The proposed method,modified Euler explicit method,and other methods known in the literature have all been used to calculate the absolute maximum error,absolute error at the last grid point of the integration interval under consideration,and computational time in seconds to test the performance.The Lorentz system was used as an example to illustrate the validity of the solution provided by the newly developed method.The method is determined to be more reliable than the commonly existing methods with the same order of convergence,as mentioned in the literature for numerical calculations and visualization of the results produced by all the methods discussed,Mat Lab-R2011b has been used. 展开更多
关键词 local truncation error CONSISTENCY computational time STABILITY lorentz system
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A joint optimization algorithm for focused energy delivery in precision electronic warfare 被引量:3
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作者 Zhong-ping Yang Shu-ning Yang +3 位作者 Qing-song Zhou Jian-yun Zhang Zhi-hui Li Zhong-rui Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第4期709-721,共13页
Focused energy delivery(FED) is a technique that can precisely bring energy to the specific region,which arouses wide attention in precision electronic warfare(PREW).This paper first proposes a joint optimization mode... Focused energy delivery(FED) is a technique that can precisely bring energy to the specific region,which arouses wide attention in precision electronic warfare(PREW).This paper first proposes a joint optimization model with respect to the locations of the array and the transmitted signals to improve the performance of FED.As the problem is nonconvex and NP-hard,particle swarm optimization(PSO) is adopted to solve the locations of the array,while designing the transmitted signals under a feasible array is considered as a unimodular quadratic program(UQP) subproblem to calculate the fitness criterion of PSO.In the PSO-UQP framework established,two methods are presented for the UQP subproblem,which are more efficient and more accurate respectively than previous works.Furthermore,a threshold value is set in the framework to determine which method to adopt to take full advantages of the methods above.Meanwhile,we obtain the maximum localization error that FED can tolerate,which is significant for implementing FED in practice.Simulation results are provided to demonstrate the effectiveness of the joint optimization algorithm,and the correctness of the maximum localization error derived. 展开更多
关键词 Focused energy delivery localization error Particle swarm optimization Precision electronic warfare Unimodular quadratic program
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A class of fully third-order accurate projection methods for solving the incompressible Navier-Stokes equations 被引量:2
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作者 Yuxin Ren Yuxi Jiang +1 位作者 Miao'er Liu Hanxin Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期542-549,共8页
In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We the... In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases. 展开更多
关键词 Incompressible Navier-Stokes equations Projection methods - Third-order scheme - local truncation error
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Error Model of Curves in GIS and Digitization Experiment
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作者 GUO Tongde WANG Jiayao WANG Guangxia 《Geo-Spatial Information Science》 2006年第4期306-310,共5页
A stochastic error process of curves is proposed as the error model to describe the errors of curves in GIS. In terms of the stochastic process, four characteristics concerning the local error of curves, namely, mean ... A stochastic error process of curves is proposed as the error model to describe the errors of curves in GIS. In terms of the stochastic process, four characteristics concerning the local error of curves, namely, mean error function, standard error function, absolute error function, and the correlation function of errors , are put forward. The total error of a curve is expressed by a mean square integral of the stochastic error process. The probabilistic meanings and geometric meanings of the characteristics mentioned above are also discussed. A scan digitization experiment is designed to check the efficiency of the model. In the experiment, a piece of contour line is digitized for more than 100 times and lots of sample functions are derived from the experiment. Finally, all the error characteristics are estimated on the basis of sample functions. The experiment results show that the systematic error in digitized map data is not negligible, and the errors of points on curves are chiefly dependent on the curvature and the concavity of the curves. 展开更多
关键词 error model of curves stochastic process local error total error digitization experiment
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Projected gradient trust-region method for solving nonlinear systems with convex constraints
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作者 JIA Chun-xia ZHU De-tong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期57-69,共13页
In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of comput... In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of computing trial directions by this method combining with the line search technique. Close to the solution set this method is locally Q-superlinearly convergent under an error bound assumption which is much weaker than the standard nonsingularity condition. 展开更多
关键词 Nonlinear equation trust region method projected gradient local error bound.
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THE HIGH ACCURACY EXPLICIT DIFFERENCE SCHEME FOR SOLVING PARABOLIC EQUATIONS 3-DIMENSION
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作者 孙鸿烈 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第7期88-93,共6页
In this paper, an explicit three_level symmetrical differencing scheme with parameters for solving parabolic partial differential equation of three_dimension will be considered. The stability condition and local trunc... In this paper, an explicit three_level symmetrical differencing scheme with parameters for solving parabolic partial differential equation of three_dimension will be considered. The stability condition and local truncation error for the scheme are r<1/2 and O( Δ t 2+ Δ x 4+ Δ y 4+ Δ z 4) ,respectively. 展开更多
关键词 parabolic partial differential equation of three_dimension implicit difference scheme explicit difference scheme local truncation error absolutely stable condition stable
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Optimized Deep Learning Model for Fire Semantic Segmentation
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作者 Songbin Li Peng Liu +1 位作者 Qiandong Yan Ruiling Qian 《Computers, Materials & Continua》 SCIE EI 2022年第9期4999-5013,共15页
Recent convolutional neural networks(CNNs)based deep learning has significantly promoted fire detection.Existing fire detection methods can efficiently recognize and locate the fire.However,the accurate flame boundary... Recent convolutional neural networks(CNNs)based deep learning has significantly promoted fire detection.Existing fire detection methods can efficiently recognize and locate the fire.However,the accurate flame boundary and shape information is hard to obtain by them,which makes it difficult to conduct automated fire region analysis,prediction,and early warning.To this end,we propose a fire semantic segmentation method based on Global Position Guidance(GPG)and Multi-path explicit Edge information Interaction(MEI).Specifically,to solve the problem of local segmentation errors in low-level feature space,a top-down global position guidance module is used to restrain the offset of low-level features.Besides,an MEI module is proposed to explicitly extract and utilize the edge information to refine the coarse fire segmentation results.We compare the proposed method with existing advanced semantic segmentation and salient object detection methods.Experimental results demonstrate that the proposed method achieves 94.1%,93.6%,94.6%,95.3%,and 95.9%Intersection over Union(IoU)on five test sets respectively which outperforms the suboptimal method by a large margin.In addition,in terms of accuracy,our approach also achieves the best score. 展开更多
关键词 Fire semantic segmentation local segmentation errors global position guidance multi-path explicit edge information interaction feature fusion
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AN ERROR-RESILIENT H.263+ CODING SCHEME FOR VIDEO TRANSMISSION OVER WIRELESS NETWORKS
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作者 Li Jian Bie Hongxia 《Journal of Electronics(China)》 2006年第6期831-836,共6页
Video transmission over wireless networks has received much attention recently for its restricted bandwidth and high bit-error rate, Based on H.263+, by reversing part stream sequences of each Group Of Block (GOB),... Video transmission over wireless networks has received much attention recently for its restricted bandwidth and high bit-error rate, Based on H.263+, by reversing part stream sequences of each Group Of Block (GOB), an error resilient scheme is presented to improve video robustness without additional bandwidth burden. Error patterns are employed to simulate Widcband Code Division Multiple Acccss,(WCDMA) channels to check out error resilience performances. Simulation results show that both subjective and objective qualities of the reconstructed images are improved remarkably. The mean Peak Signal to Noise Ratio (PSNR) is increased by 0.5dB, and the highest increment is 2dB. 展开更多
关键词 Wireless networks Error detection Error resilient Error localization RESYNCHRONIZATION
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A MULTIPLE INTELLIGENT AGENT SYSTEM FOR CREDIT RISK PREDICTION VIA AN OPTIMIZATION OF LOCALIZED GENERALIZATION ERROR WITH DIVERSITY 被引量:2
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作者 Daniel S. YEUNG Wing W. Y. NG +3 位作者 Aki P. F. CHAN Patrick P. K. CHAN Michael FIRTH Eric C. C. TSANG 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2007年第2期166-180,共15页
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk pred... Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset. 展开更多
关键词 Credit rating business intelligence localized generalization error multiple classifier system feature grouping
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Local a priori/a posteriori error estimates of conforming finite elements approximation for Steklov eigenvalue problems 被引量:2
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作者 YANG YiDu BI Hai 《Science China Mathematics》 SCIE 2014年第6期1319-1329,共11页
Based on the work of Xu and Zhou(2000),this paper makes a further discussion on conforming finite elements approximation for Steklov eigenvalue problems,and proves a local a priori error estimate and a new local a pos... Based on the work of Xu and Zhou(2000),this paper makes a further discussion on conforming finite elements approximation for Steklov eigenvalue problems,and proves a local a priori error estimate and a new local a posteriori error estimate in ||·||1,Ω0 norm for conforming elements eigenfunction,which has not been studied in existing literatures. 展开更多
关键词 Steklov eigenvalue problems conforming finite elements local error estimates
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OPTIMAL INTERIOR AND LOCAL ERROR ESTIMATES OF A RECOVERED GRADIENT OF LINEAR ELEMENTS ON NONUNIFORM TRIANGULATIONS
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作者 I. Hlavacek M. Krizek(Mathematical Institute, Zitna 25, CZ-11567, Prague 1, Czech Republic) 《Journal of Computational Mathematics》 SCIE CSCD 1996年第4期345-362,共18页
We examine a simple averaging formula for the gradieni of linear finite elemelitsin Rd whose interpolation order in the Lq-norm is O(h2) for d < 2q and nonuniformtriangulations. For elliptic problems in R2 we deriv... We examine a simple averaging formula for the gradieni of linear finite elemelitsin Rd whose interpolation order in the Lq-norm is O(h2) for d < 2q and nonuniformtriangulations. For elliptic problems in R2 we derive an interior superconvergencefor the averaged gradient over quasiuniform triangulations. Local error estimatesup to a regular part of the boundary and the effect of numerical integration arealso investigated. 展开更多
关键词 Math Pro OPTIMAL INTERIOR AND local ERROR ESTIMATES OF A RECOVERED GRADIENT OF LINEAR ELEMENTS ON NONUNIFORM TRIANGULATIONS
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Algorithm based on local breeding of growing modes for convection-allowing ensemble forecasting 被引量:3
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作者 Chaohui CHEN Xiang LI +2 位作者 Hongrang HE Jie XIANG Shenjia MA 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第4期462-472,共11页
We propose a method based on the local breeding of growing modes(LBGM) considering strong local weather characteristics for convection-allowing ensemble forecasting. The impact radius was introduced in the breeding of... We propose a method based on the local breeding of growing modes(LBGM) considering strong local weather characteristics for convection-allowing ensemble forecasting. The impact radius was introduced in the breeding of growing modes to develop the LBGM method. In the local breeding process, the ratio between the root mean square error(RMSE) of local space forecast at each grid point and that of the initial full-field forecast is computed to rescale perturbations. Preliminary evaluations of the method based on a nature run were performed in terms of three aspects: perturbation structure, spread,and the RMSE of the forecast. The experimental results confirm that the local adaptability of perturbation schemes improves after rescaling by the LBGM method. For perturbation physical variables and some near-surface meteorological elements, the LBGM method could increase the spread and reduce the RMSE of forecast,improving the performance of the ensemble forecast system.In addition, different from those existing methods of global orthogonalization approach, this new initial-condition perturbation method takes into full consideration the local characteristics of the convective-scale weather system, thus making convectionallowing ensemble forecast more accurate. 展开更多
关键词 Convection-allowing ensemble forecasting local breeding of growing modes Perturbation structure Spread Root mean square error of forecast
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EFFICIENT SIXTH ORDER P-STABLE METHODS WITH MINIMAL LOCAL TRUNCATION ERROR FOR y"=f(x,y)
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作者 Kai-li Xiang R.M.Thomas 《Journal of Computational Mathematics》 SCIE CSCD 2002年第2期175-184,共10页
A family of symmetric (hybrid) two step sixth P-stable methods for the accurate numerical integration of second order periodic initial value problems have been considered in this paper. These methods, which require on... A family of symmetric (hybrid) two step sixth P-stable methods for the accurate numerical integration of second order periodic initial value problems have been considered in this paper. These methods, which require only three (new) function evaluation per iteration and per step integration. These methods have minimal local truncation error (LTE) and smaller phase-lag of sixth order than some sixth orders P-stable methods in [1-3,10-11]. The theoretical and numerical results show that these methods in this paper are more accurate and efficient than some methods proposed in [1-3,10]. 展开更多
关键词 second order periodic initial value problems P-stable PHASE-LAG local truncation error
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TWO-STEP SCHEME FOR BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS
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作者 Qiang Han Shaolin Ji 《Journal of Computational Mathematics》 SCIE CSCD 2023年第2期287-304,共18页
In this paper,a stochastic linear two-step scheme has been presented to approximate backward stochastic differential equations(BSDEs).A necessary and sufficient condition is given to judge the L 2-stability of our num... In this paper,a stochastic linear two-step scheme has been presented to approximate backward stochastic differential equations(BSDEs).A necessary and sufficient condition is given to judge the L 2-stability of our numerical schemes.This stochastic linear two-step method possesses a family of 3-order convergence schemes in the sense of strong stability.The coefficients in the numerical methods are inferred based on the constraints of strong stability and n-order accuracy(n∈N^(+)).Numerical experiments illustrate that the scheme is an efficient probabilistic numerical method. 展开更多
关键词 Backward stochastic differential equation Stochastic linear two-step scheme local truncation error Stability and convergence
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Shamanskii-Like Levenberg-Marquardt Method with a New Line Search for Systems of Nonlinear Equations 被引量:10
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作者 CHEN Liang MA Yanfang 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2020年第5期1694-1707,共14页
To save the calculations of Jacobian,a multi-step Levenberg-Marquardt method named Shamanskii-like LM method for systems of nonlinear equations was proposed by Fa.Its convergence properties have been proved by using a... To save the calculations of Jacobian,a multi-step Levenberg-Marquardt method named Shamanskii-like LM method for systems of nonlinear equations was proposed by Fa.Its convergence properties have been proved by using a trust region technique under the local error bound condition.However,the authors wonder whether the similar convergence properties are still true with standard line searches since the direction may not be a descent direction.For this purpose,the authors present a new nonmonotone m-th order Armijo type line search to guarantee the global convergence.Under the same condition as trust region case,the convergence rate also has been shown to be m+1 by using this line search technique.Numerical experiments show the new algorithm can save much running time for the large scale problems,so it is efficient and promising. 展开更多
关键词 Armijo line search Levenberg-Marquardt method local error bound condition systems of nonlinear equations unconstrained optimization
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Numerical Integration Over Implicitly Defined Domains with Topological Guarantee 被引量:2
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作者 Tianhui Yang Ammar Qarariyah +1 位作者 Hongmei Kang Jiansong Deng 《Communications in Mathematics and Statistics》 SCIE 2019年第4期459-474,共16页
Numerical integration over the implicitly defined domains is challenging due to topological variances of implicit functions.In this paper,we use interval arithmetic to identify the boundary of the integration domain e... Numerical integration over the implicitly defined domains is challenging due to topological variances of implicit functions.In this paper,we use interval arithmetic to identify the boundary of the integration domain exactly,thus getting the correct topology of the domain.Furthermore,a geometry-based local error estimate is explored to guide the hierarchical subdivision and save the computation cost.Numerical experiments are presented to demonstrate the accuracy and the potential of the proposed method. 展开更多
关键词 Isogeometric analysis Numerical integration Implicitly defined domains Topological guarantee Interval arithmetic local error estimate Hierarchical subdivision
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On the Linear Convergence of the Approximate Proximal Splitting Method for Non-smooth Convex Optimization
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作者 Mojtaba Kadkhodaie Maziar Sanjabi Zhi-Quan Luo 《Journal of the Operations Research Society of China》 EI 2014年第2期123-141,共19页
Consider the problem of minimizing the sum of two convex functions,one being smooth and the other non-smooth.In this paper,we introduce a general class of approximate proximal splitting(APS)methods for solving such mi... Consider the problem of minimizing the sum of two convex functions,one being smooth and the other non-smooth.In this paper,we introduce a general class of approximate proximal splitting(APS)methods for solving such minimization problems.Methods in the APS class include many well-known algorithms such as the proximal splitting method,the block coordinate descent method(BCD),and the approximate gradient projection methods for smooth convex optimization.We establish the linear convergence of APS methods under a local error bound assumption.Since the latter is known to hold for compressive sensing and sparse group LASSO problems,our analysis implies the linear convergence of the BCD method for these problems without strong convexity assumption. 展开更多
关键词 Convex optimization Proximal splitting method Block coordinate descent method Convergence rate analysis local error bound
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