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An Adaptive Cubic Regularisation Algorithm Based on Affine Scaling Methods for Constrained Optimization
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作者 PEI Yonggang WANG Jingyi 《应用数学》 北大核心 2026年第1期258-277,共20页
In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the op... In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the optimality conditions of the problem,we introduce appropriate affine matrix and construct an affine scaling ARC subproblem with linearized constraints.Composite step methods and reduced Hessian methods are applied to tackle the linearized constraints.As a result,a standard unconstrained ARC subproblem is deduced and its solution can supply sufficient decrease.The fraction to the boundary rule maintains the strict feasibility(for nonnegative constraints on variables)of every iteration point.Reflection techniques are employed to prevent the iterations from approaching zero too early.Under mild assumptions,global convergence of the algorithm is analysed.Preliminary numerical results are reported. 展开更多
关键词 Constrained optimization Adaptive cubic regularisation Affine scaling Global convergence
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Converging assemblies:A putative building block for brain function and for interfacing with the brain
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作者 Eran Stark Lidor Spivak 《Neural Regeneration Research》 2026年第3期1124-1125,共2页
The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they ... The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they exhibit dense interconnectivity(Braitenburg and Schüz,1998;Campagnola et al.,2022).The strength and probability of connectivity depend on cell type,inter-neuronal distance,and species.Still,every cortical neuron receives input from thousands of other neurons while transmitting output to a similar number of neurons.Second,communication between neurons occurs primarily via chemical or electrical synapses. 展开更多
关键词 cortical neuron INTERCONNECTIVITY neuronal networks functional modules dense interconnectivity braitenburg artificial systemsthese converging assemblies biological neuronal networks
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CONVERGENCY OF THE MAXIMUM OF PERIODOGRAM 被引量:1
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作者 HE Shuyuan(Department of Probability and Statistics, Peking University, Beijing 100871,China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1995年第3期260-269,共10页
CONVERGENCYOFTHEMAXIMUMOFPERIODOGRAM¥HEShuyuan(DepartmentofProbabilityandStatistics,PekingUniversity,Beijing... CONVERGENCYOFTHEMAXIMUMOFPERIODOGRAM¥HEShuyuan(DepartmentofProbabilityandStatistics,PekingUniversity,Beijing100871,China)Abst... 展开更多
关键词 STATIONARY sequence PERIODOGRAM trigonometric POLYNOMIAL STRONG convergence.
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A Modified PRP-HS Hybrid Conjugate Gradient Algorithm for Solving Unconstrained Optimization Problems 被引量:1
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作者 LI Xiangli WANG Zhiling LI Binglan 《应用数学》 北大核心 2025年第2期553-564,共12页
In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradien... In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradient method.Under the condition of standard Wolfe line search,the proposed search direction is the descent direction.For general nonlinear functions,the method is globally convergent.Finally,numerical results show that the proposed method is efficient. 展开更多
关键词 Conjugate gradient method Unconstrained optimization Sufficient descent condition Global convergence
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Impact speed and angle constrained guidance law for unpowered gliding vehicle 被引量:2
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作者 Xinwan KONG Cheng ZHANG Fenfen XIONG 《Chinese Journal of Aeronautics》 2025年第4期408-419,共12页
In this paper,a novel guidance law is proposed which can achieve the desired impact speed and angle simultaneously for unpowered gliding vehicles.A guidance law with only impact angle constraint is used to produce the... In this paper,a novel guidance law is proposed which can achieve the desired impact speed and angle simultaneously for unpowered gliding vehicles.A guidance law with only impact angle constraint is used to produce the guidance profile,and its convergence in the varying speed scenario is proved.A relationship between flight states,guidance input and impact speed is established.By applying the fixed-time convergence control theory of error dynamics,an impact speed corrector is built with the above guidance profile,which can implement impact speed correction without affecting the impact angle constraint.Numerical simulations with various impact speed and angle constraints are conducted to demonstrate the performance of the proposed guidance law,and the robustness is also verified by Monte Carlo tests. 展开更多
关键词 Multi-constrained guidance Speed control Error dynamics Fixed-time convergence Unpowered vehicle
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Irreversibility analysis and multiple cubic regression based efficiency evaluation of ternary nanofluids(TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O)via converging/diverging channels 被引量:1
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作者 Siddhant Taneja Sapna Sharma Bhuvaneshvar Kumar 《Acta Mechanica Sinica》 2025年第6期63-75,共13页
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d... This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid. 展开更多
关键词 Converging/Diverging channels Ternary nanofluids Multiple cubic regression Entropy generation
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Distributed Robust Predefined-Time Algorithm for Seeking Nash Equilibrium in MASs 被引量:1
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作者 Jing-Zhe Xu Zhi-Wei Liu +2 位作者 Ming-Feng Ge Yan-Wu Wang Dingxin He 《IEEE/CAA Journal of Automatica Sinica》 2025年第5期1053-1055,共3页
Dear Editor,This letter presents a solution to the problem of seeking Nash equilibrium(NE)in a class of non-cooperative games of multi-agent systems(MASs)subject to the input disturbance and the networked communicatio... Dear Editor,This letter presents a solution to the problem of seeking Nash equilibrium(NE)in a class of non-cooperative games of multi-agent systems(MASs)subject to the input disturbance and the networked communication.To this end,a novel distributed robust predefined-time algorithm is proposed,which ensures the precise convergence of agent states to the NE within a settling time that can be directly determined by adjusting one or more parameters.The proposed algorithm employs an integral sliding mode strategy to effectively reject disturbances.Additionally,a consensus-based estimator is designed to overcome the challenge of limited information availability,where each agent can only access information from its directly connected neighbors,which conflicts with the computation of the cost function that requires information from all agents.Finally,a numerical example is provided to demonstrate the algorithm's effectiveness and performance. 展开更多
关键词 seeking nash convergence agent states multi agent systems integral sliding mode strateg non cooperative games Nash equilibrium distributed algorithm robust control
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柴油/正戊醇燃料发动机CFD模型的研究
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作者 叶卓 林贤坤 《广西科技大学学报》 2025年第3期9-16,共8页
作为清洁且可再生的替代能源,醇类燃料对于优化发动机的排放性能具有显著的效果。通过数值模拟计算发动机运行过程,能够避免试验研究存在的设备开发投入高、试验周期长等问题。本文使用CONVERGE软件,根据使用柴油/正戊醇燃料的YC4Y22型... 作为清洁且可再生的替代能源,醇类燃料对于优化发动机的排放性能具有显著的效果。通过数值模拟计算发动机运行过程,能够避免试验研究存在的设备开发投入高、试验周期长等问题。本文使用CONVERGE软件,根据使用柴油/正戊醇燃料的YC4Y22型玉柴柴油发动机试验结果,分析三维计算流体力学(computational fluid dynamics, CFD),合理设置各个计算模块,建立了发动机简化三维几何模型。在该模型的基础上,分析部分参数对模型预测发动机缸内平均压力及排放的影响。结果表明:热力学温度边界的设置对模型预测缸内平均压力影响不大,初始热力学温度的设置能有效修正缸内平均压力曲线;模型HC和CO的排放随着活塞边界热力学温度和缸盖边界热力学温度的升高而下降,随着壁面边界热力学温度的升高先下降后升高;同时HC和CO的排放随着喷油器深度尺寸的增大而下降,随着直径尺寸的增大而升高。综合以上结果修正参数,对比柴油/正戊醇燃料发动机的燃烧和排放两种特性,建立了合理的发动机计算流体力学模型,用于分析和优化不同因素对柴油/正戊醇混合燃料发动机燃烧和排放特性的影响。 展开更多
关键词 正戊醇 柴油机 计算流体力学(CFD)模型 CONVERGE 模型修正
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A Class of Parallel Algorithm for Solving Low-rank Tensor Completion
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作者 LIU Tingyan WEN Ruiping 《应用数学》 北大核心 2025年第4期1134-1144,共11页
In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice ... In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice matrix under unfold operator,and then the fold operator is used to form the next iteration tensor such that the computing time can be decreased.In theory,we analyze the global convergence of the algorithm.In numerical experiment,the simulation data and real image inpainting are carried out.Experiment results show the parallel algorithm outperform its original algorithm in CPU times under the same precision. 展开更多
关键词 Tensor completion Low-rank CONVERGENCE Parallel algorithm
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A Comparison of Stability Analysis Results for an Open Pit-dump System Using Limit Equilibrium and Finite Element Modelling Methods
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作者 Alexander Evgenievich Rumyantsev Yuriy Yurievich Golovchenko +3 位作者 Anton Vladimirovich Fedoseev Andrey Viktorovich Trofimov Maksim Alexandrovich Sonnov CHEN Jia 《有色金属(中英文)》 北大核心 2025年第12期2307-2317,共11页
The paper considers the methodology for a comprehensive analysis of the stability of an open pit-dump system,using limit equilibrium(LEM)and finite element(FEM)methods in the Russian CAE(computer-aided engineering)sof... The paper considers the methodology for a comprehensive analysis of the stability of an open pit-dump system,using limit equilibrium(LEM)and finite element(FEM)methods in the Russian CAE(computer-aided engineering)software Fidesys.It briefly highlights the issues of comparing limit equilibrium methods using the VNIMI(Research Institute of Geomechanics and Mine Surveying-Intersectoral Scientific Center"VNIMI")methodology and a specialized software product with numerical methods.The main focus of this study is to compare the results of the stability analysis in the volumetric model of the open pit-dump system using limit equilibrium and finite element methods in the CAE software Fidesys.It was found that,when modeling the combined operation of an open pit-dump system in complex terrain,both methods should be used,as each has its own advantages.The finite element method,for instance,has certain features that are not present in the calculations using the limit equilibrium approach.As a key scientific contribution,this paper introduces an automation program for calculating the stability of open-pit walls using the limit equilibrium method in CAE Fidesys,which was not previously integrated in the original software.The calculations performed with the use of this newly developed module were compared to those obtained from other widely used software solutions available on the market.The findings demonstrate a remarkable level of convergence in the calculation results for all relevant parameters,including the safety factor,localization,instability type,and deformation.The proposed approach i mproves the accuracy of calculati ons and ensures consistency between the higher stress design zones and the actual deformation and fracture patterns.It also enhances the ability to predict the behavior of rock mass when calculating stability parameters for facilities,both during operation and desi gn. 展开更多
关键词 limit equilibrium numerical modeling safety factor stability GEOMECHANICS convergence of calculations CAE Fidesys
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Smoluchowski-Kramers Approximation for Stochastic Differential Equations under Discretization
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作者 Li Ge 《应用概率统计》 北大核心 2025年第4期622-635,共14页
This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–M... This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–Maruyama discretization and derive its convergence rate.In particular,the solution of the discretized system converges to the solution of the first-order limit equation in the mean-square sense,and this convergence is independent of the order in which the mass parameterμand the step size h tend to zero. 展开更多
关键词 stochastic differential equations Smoluchowski-Kramers approximation driftimplicit Euler-Maruyama scheme convergence rate
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Fixed-time Target-guided Coordinate Control of Unmanned Surface Vehicles Based on Dynamic Surface Control
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作者 LI Chao−yi XU Hai−xiang +2 位作者 YU Wen−zhao DU Zhe DING Ya−nan 《船舶力学》 北大核心 2025年第6期849-862,共14页
This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only b... This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only be obtained by some USVs.In order to achieve semi-encirclement tracking of noncooperative targets under maritime security conditions,a fixed-time tracking control method based on dynamic surface control(DSC)is proposed in this paper.Firstly,a novel TACC architecture with decoupled kinematic control law and decoupled kinetic control law was designed to reduce the complexity of control system design.Secondly,the proposed DSC-based target-guided kinematic control law including tracking points pre-allocation strategy and sigmoid artificial potential functions(SigAPFs)can avoid collisions during tracking process and optimize kinematic control output.Finally,a fixed-time TACC system was proposed to achieve fast convergence of kinematic and kinetics errors.The effectiveness of the proposed TACC approach in improving target tracking safety and reducing control output chattering was verified by simulation comparison results. 展开更多
关键词 unmanned surface vehicle distributed control target-guided coordinate control fixed-time convergence dynamic surface control
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Symmetric Periodic Solution of Linear Periodic Matrix Equations via BCR Algorithm
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作者 MA Changfeng XIE Yajun 《数学进展》 北大核心 2025年第4期881-890,共10页
Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently so... Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently solving linear systems Aα=b.The objective of this paper is to provide one new iterative algorithm based on BCR method to find the symmetric periodic solutions of linear periodic matrix equations.This kind of periodic matrix equations has not been dealt with yet.This iterative method is guaranteed to converge in a finite number of steps in the absence of round-off errors.Some numerical results are performed to illustrate the efficiency and feasibility of new method. 展开更多
关键词 periodic matrix equation biconjugate residual method symmetric periodic solution convergence analysis
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Large Deviations for Fractional Stochastic Heat Equation with Gaussian Noise Rough in Space
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作者 WANG Zhi LIU Junfeng 《数学进展》 北大核心 2025年第6期1368-1392,共25页
In this paper we study the Freidlin-Wentzell's large deviation principle for the following nonlinear fractional stochastic heat equation driven by Gaussian noise∂/∂tu^(ε)=D_(δ)^(α)(t,x)+√εσ(u^(ε)(t,x))W(t,x... In this paper we study the Freidlin-Wentzell's large deviation principle for the following nonlinear fractional stochastic heat equation driven by Gaussian noise∂/∂tu^(ε)=D_(δ)^(α)(t,x)+√εσ(u^(ε)(t,x))W(t,x),(t,x)∈[0,T]×R,where D_(δ)^(α)is a nonlocal fractional differential operator and W is the Gaussian noise which is white in time and behaves as a fractional Brownian motion with Hurst index H satisfying 3-α/4<H<1/2,in the space variable.The weak convergence approach plays an important role. 展开更多
关键词 fractional stochastic heat equation fractional Brownian motion large deviation principle weak convergence
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence Higher-order method Extended Newton iteration Computational efficiency
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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THREE INERTIAL ACCELERATION ALGORITHMS FOR SOLVING NON-MONOTONE EQUILIBRIUM PROBLEMS IN HILBERT SPACES
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作者 Yonghong YAO Olaniyi S.IYIOLA Yekini SHEHU 《Acta Mathematica Scientia》 2025年第4期1674-1700,共27页
Several results on iterative methods for equilibrium problems have been proposed and studied in the literature.Most of these results are obtained when the associated bifunction of the equilibrium problem is either a m... Several results on iterative methods for equilibrium problems have been proposed and studied in the literature.Most of these results are obtained when the associated bifunction of the equilibrium problem is either a monotone or pseudomonotone operator.Results on iterative methods for equilibrium problems without monotonicity conditions on the bifunction are still few in the literature.In this paper,we study equilibrium problems for which the underlined bifunction is not assumed any form of monotonicity.We propose two weakly convergent iterative algorithms and one strongly convergent algorithm.We obtain our convergence results without assuming either monotonicity or pseudomonotonicity condition on the bifunction.Our proposed algorithms are tested numerically to be more efficient and faster than some few available algorithms for equilibrium problems without monotonicity in the literature. 展开更多
关键词 equilibrium problem nonmonotone bifunction weak convergence strong convergence
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Exploring Economic Convergence Within the Silk Road Sphere:An Analysis of Central Asian Turkic Republics,China,Pakistan,and Key Diplomatic Allies
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作者 Abdul Wajid 《Management Studies》 2025年第3期135-146,共12页
This study looks at how the Belt and Road Initiative(BRI)has affected the economic convergence of the Central Asian Turkic Republics,China,Pakistan,and their major diplomatic partners in the Silk Road region.Using bet... This study looks at how the Belt and Road Initiative(BRI)has affected the economic convergence of the Central Asian Turkic Republics,China,Pakistan,and their major diplomatic partners in the Silk Road region.Using beta and sigma convergence models over a predetermined time frame,the research evaluates economic alignment trends statistically and looks into how trade openness,FDI,and human capital affect the convergence process.The research attempts to discover larger causes of convergence,such as institutional quality and geopolitical closeness,by combining econometric analysis with regional economic dynamics.The purpose of the results is to provide policy suggestions that will improve equitable and sustainable economic convergence inside the Silk Road circle,promoting international cooperation and growth. 展开更多
关键词 economic convergence Silk Road beta and sigma convergence models foreign direct investment(FDI) trade transparency human capital development
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Comparing perch availability and perch use between African dwarf chameleon(Bradypodion)ecomorphs
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作者 Jody M.Barends Melissa A.Petford Krystal A.Tolley 《Current Zoology》 2025年第5期633-644,共12页
Adaptation to different environments can lead to local adaptations that facilitate morphological divergence between closely related taxa,potentially leading to speciation.Quantifying habitat variation can thus provide... Adaptation to different environments can lead to local adaptations that facilitate morphological divergence between closely related taxa,potentially leading to speciation.Quantifying habitat variation can thus provide valuable insights into evolutionary processes.Arboreal dwarf chameleons of the genus Bradypodion exhibit 3 distinct ecomorphological forms:forest,shrub,and“little brown chameleons”(LBCs).It is assumed these ecomorphs are the result of convergence among species that are in similar habitats regardless of ancestry,or in some cases,morphological conservatism and retention of an ancestral form that is adapted to a shared habitat type.If so,then the habitat of different ecomorphs would differ in vegetation structure.Our results show that vegetation structure in fynbos/grassy habitats is characterized by significantly narrower perches than shrubby habitats,but both have a largely vertical perch orientation.In contrast,forests have significantly fewer vertical perches than fynbos/grassy habitats with significantly thicker diameter perches.Accordingly,LBC and shrub species used more vertically oriented perches than forest species,suggesting that perch use corresponds with the most widely available perch angles.Although LBC chameleons used the smallest diameter perches,when corrected for body size,there was no difference in perch diameter among ecomorphs.These results suggest that the body size of LBC chameleons is constrained by the prevalence of small-diameter perches in their habitat.Species in habitats with wider perches attain larger body size.These findings support the notion that variation in perch structure is critical for phenotypic convergence that has resulted in the 3 Bradypodion ecomorphs. 展开更多
关键词 adaptation convergence DIVERGENCE habitat use morphology reptiles
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