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An Effective Meshless Approach for Inverse Cauchy Problems in 2D and 3D Electroelastic Piezoelectric Structures
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作者 Ziqiang Bai Wenzhen Qu Guanghua Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2955-2972,共18页
In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within... In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within each sub-domain,explicit formulas for the necessary partial derivatives of the partial differential equations(PDEs)can be obtained through the application of Taylor series expansion and moving-least square approximation methods.Consequently,the method generates a sparse coefficient matrix,exhibiting a banded structure,making it highly advantageous for large-scale engineering computations.In this study,we present the application of the GFDM to numerically solve inverse Cauchy problems in two-and three-dimensional piezoelectric structures.Through our preliminary numerical experiments,we demonstrate that the proposed GFDMapproach shows great promise for accurately simulating coupled electroelastic equations in inverse problems,even with 3%errors added to the input data. 展开更多
关键词 Generalized finite difference method meshless method inverse Cauchy problems piezoelectric problems electroelastic analysis
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems
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作者 Chein-Shan Liu Chung-Lun Kuo Chih-Wen Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3189-3208,共20页
To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection techniq... To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit function.We can quickly determine the optimal values of the parameters within a preferred rage using the golden section search algorithm.The novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical examples.Moreover,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being ill-posed.The optimal MQ-RBF is extremely accurate.We further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11). 展开更多
关键词 Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method
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Association of preschool children behavior and emotional problems with the parenting behavior of both parents
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作者 Su-Mei Wang Shuang-Qin Yan +4 位作者 Fang-Fang Xie Zhi-Ling Cai Guo-Peng Gao Ting-Ting Weng Fang-Biao Tao 《World Journal of Clinical Cases》 SCIE 2024年第6期1084-1093,共10页
BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.... BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors. 展开更多
关键词 CHILDREN Preschool age PARENTING BEHAVIORAL Parenting problems
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Dirac method for nonlinear and non-homogenous boundary value problems of plates
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作者 Xiaoye MAO Jiabin WU +2 位作者 Junning ZHANG Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期15-38,共24页
The boundary value problem plays a crucial role in the analytical investigation of continuum dynamics. In this paper, an analytical method based on the Dirac operator to solve the nonlinear and non-homogeneous boundar... The boundary value problem plays a crucial role in the analytical investigation of continuum dynamics. In this paper, an analytical method based on the Dirac operator to solve the nonlinear and non-homogeneous boundary value problem of rectangular plates is proposed. The key concept behind this method is to transform the nonlinear or non-homogeneous part on the boundary into a lateral force within the governing function by the Dirac operator, which linearizes and homogenizes the original boundary, allowing one to employ the modal superposition method for obtaining solutions to reconstructive governing equations. Once projected into the modal space, the harmonic balance method(HBM) is utilized to solve coupled ordinary differential equations(ODEs)of truncated systems with nonlinearity. To validate the convergence and accuracy of the proposed Dirac method, the results of typical examples, involving nonlinearly restricted boundaries, moment excitation, and displacement excitation, are compared with those of the differential quadrature element method(DQEM). The results demonstrate that when dealing with nonlinear boundaries, the Dirac method exhibits more excellent accuracy and convergence compared with the DQEM. However, when facing displacement excitation, there exist some discrepancies between the proposed approach and simulations;nevertheless, the proposed method still accurately predicts resonant frequencies while being uniquely capable of handling nonuniform displacement excitations. Overall, this methodology offers a convenient way for addressing nonlinear and non-homogenous plate boundaries. 展开更多
关键词 rectangular plate Dirac operator nonlinear boundary time-dependent boundary boundary value problem
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Problems and Development Suggestions of Nature Education in Jiangxi Province
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作者 Hua LI Shinan XIANG Feiping CHEN 《Meteorological and Environmental Research》 2024年第1期46-47,56,共3页
The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has... The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has great potential and advantages.This paper introduces the development conditions of nature education in Jiangxi Province,summarizes the problems existing in the development of nature education in Jiangxi Province from the aspects of the types of nature education and the construction of nature education base,such as simple content and single form,imperfect infrastructure and lack of professionals,and puts forward some suggestions on the development of nature education in Jiangxi Province. 展开更多
关键词 Jiangxi Province Nature education PROBLEM Development suggestion
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Prevalence of emotional and behavioral problems among schoolchildren in Herat City,Afghanistan 被引量:1
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作者 Mina Alekozay Aziz-ur-Rahman Niazi Abdul Fattah Najm 《Global Health Journal》 2023年第1期55-60,共6页
Background:The prevalence of pediatric mental illnesses has been increasing in recent years,with a great potential to impact on individual's functionality and adaptation in adulthood.Objective:This study aims to a... Background:The prevalence of pediatric mental illnesses has been increasing in recent years,with a great potential to impact on individual's functionality and adaptation in adulthood.Objective:This study aims to assess emotional and behavioral problems among schoolchildren in Herat City of Afghanistan.Methods:This cross-sectional study was conducted on schoolchildren(grade 5-10),between September and November 2021.Sociodemographic data was collected using a paper-based 14-item structured questionnaire.Data on emotional and behavioral problems was collected using the Strengths and Difficulties Questionnaire(SDQ)based on teachers'and children's report.Statistical analyses were performed in IBM SPSS Statistics(version 27).Results:A total of 418 students,including 190(45.5%)males and 228(54.5%)females with a mean age of 14.1±1.7(11-<18)years were included in the study.The prevalence of students*self-reported total difficulties and prosocial problem were 5.7%and 1.2%,respectively.An insignificant difference was observed between mean total difficulties scores between students'self-reported and teachers'reported SDQ.Gender,grade,concern about shortage of food,and concern about losing house were significantly predicting students'self-reported total difficulties scores.Conclusion:This is the first study to report the prevalence of emotional and behavioral problems among schoolchildren in Herat City,Afghanistan.This,together with relevant global literature,highlight the need to address pediatric mental health,and provide services aimed at preventing,and treating children with these prob­lems around the world. 展开更多
关键词 Behavioral problems Emotional problems Strength and Difficulties Questionnaire(SDQ) SCHOOLCHILDREN Herat AFGHANISTAN
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基于YOLOv5s和Android部署的电气设备识别
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作者 廖晓辉 谢子晨 路铭硕 《郑州大学学报(工学版)》 北大核心 2024年第1期122-128,共7页
针对变电站多种电气设备实时检测的需求,提出了一种基于改进YOLOv5s的电气设备识别方法,并设计基于Android部署的电气设备识别APP,以便对电气设备进行识别与学习。以电力变压器、绝缘子串等6种常见变电站电气设备为例构建图像数据集。... 针对变电站多种电气设备实时检测的需求,提出了一种基于改进YOLOv5s的电气设备识别方法,并设计基于Android部署的电气设备识别APP,以便对电气设备进行识别与学习。以电力变压器、绝缘子串等6种常见变电站电气设备为例构建图像数据集。数据集进行图像预处理后对YOLOv5s算法进行改进。通过引入C2f模块提高小目标检测精度,采用Soft-NMS提高检测框筛选能力,减少漏检和误检的情况,使用改进后的算法对数据集进行模型训练。将训练好的识别网络模型通过TensorFlow Lite框架进行模型部署,设计电气设备识别APP。经验证,改进后的变电站电气设备识别网络模型mAP稳定在91.6%,与原模型相比提高了3.3百分点。部署后的APP具有设备识别和设备介绍等界面,使用移动端进行识别时每张图片识别时间都小于1 s,具有较快的识别速度和较高的识别精度,可以高效地实现变电站电气设备的实时检测与设备学习。 展开更多
关键词 电气设备 改进YOLOv5s andROID TensorFlow Lite 图像识别
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Use the Power of a Genetic Algorithm to Maximize and Minimize Cases to Solve Capacity Supplying Optimization and Travelling Salesman in Nested Problems
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作者 Ali Abdulhafidh Ibrahim Hajar Araz Qader Nour Ai-Huda Akram Latif 《Journal of Computer and Communications》 2023年第3期24-31,共8页
Using Genetic Algorithms (GAs) is a powerful tool to get solution to large scale design optimization problems. This paper used GA to solve complicated design optimization problems in two different applications. The ai... Using Genetic Algorithms (GAs) is a powerful tool to get solution to large scale design optimization problems. This paper used GA to solve complicated design optimization problems in two different applications. The aims are to implement the genetic algorithm to solve these two different (nested) problems, and to get the best or optimization solutions. 展开更多
关键词 Genetic Algorithm Capacity Supplying Optimization Traveling Salesman Problem Nested problems
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Reflections on,and Improvements of,the Mediation Functions of People's Assessors
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作者 Wang Gali 《Contemporary Social Sciences》 2023年第6期20-32,共13页
Legislatively,the people’s assessors are defined as individuals who share judicial power.However,in the context of dispute resolutions,their role is restricted by the courts,which affects the extent of their assessor... Legislatively,the people’s assessors are defined as individuals who share judicial power.However,in the context of dispute resolutions,their role is restricted by the courts,which affects the extent of their assessorial activities.It is imperative to reconsider the implications of the people’s assessors’deep involvement in mediation from the standpoint of societal division of labor.To enhance this division of labor,it is advisable that the people’s assessors relinquish their mediation roles.It is necessary to redefine the distinctions between people’s assessors,judges,and people’s mediators,including specially invited mediators.This would not only make up the deficiencies in the role of professional judges but also relieve the tension between judicial professionalism and popular accountability. 展开更多
关键词 social division of labor assessor system mediation function REFLECTION improvement
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CQFFA:A Chaotic Quasi-oppositional Farmland Fertility Algorithm for Solving Engineering Optimization Problems
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作者 Farhad Soleimanian Gharehchopogh Mohammad H.Nadimi-Shahraki +2 位作者 Saeid Barshandeh Benyamin Abdollahzadeh Hoda Zamani 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第1期158-183,共26页
Farmland Fertility Algorithm(FFA)is a recent nature-inspired metaheuristic algorithm for solving optimization problems.Nevertheless,FFA has some drawbacks:slow convergence and imbalance of diversification(exploration)... Farmland Fertility Algorithm(FFA)is a recent nature-inspired metaheuristic algorithm for solving optimization problems.Nevertheless,FFA has some drawbacks:slow convergence and imbalance of diversification(exploration)and intensification(exploitation).An adaptive mechanism in every algorithm can achieve a proper balance between exploration and exploitation.The literature shows that chaotic maps are incorporated into metaheuristic algorithms to eliminate these drawbacks.Therefore,in this paper,twelve chaotic maps have been embedded into FFA to find the best numbers of prospectors to increase the exploitation of the best promising solutions.Furthermore,the Quasi-Oppositional-Based Learning(QOBL)mechanism enhances the exploration speed and convergence rate;we name a CQFFA algorithm.The improvements have been made in line with the weaknesses of the FFA algorithm because the FFA algorithm has fallen into the optimal local trap in solving some complex problems or does not have sufficient ability in the intensification component.The results obtained show that the proposed CQFFA model has been significantly improved.It is applied to twenty-three widely-used test functions and compared with similar state-of-the-art algorithms statistically and visually.Also,the CQFFA algorithm has evaluated six real-world engineering problems.The experimental results showed that the CQFFA algorithm outperforms other competitor algorithms. 展开更多
关键词 Nature-inspired algorithm Farmland fertility algorithm Chaotic maps Quasi Engineering optimization problems
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Solving Geometry Problems via Feature Learning and Contrastive Learning of Multimodal Data
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作者 Pengpeng Jian Fucheng Guo +1 位作者 Yanli Wang Yang Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1707-1728,共22页
This paper presents an end-to-end deep learning method to solve geometry problems via feature learning and contrastive learning of multimodal data.A key challenge in solving geometry problems using deep learning is to... This paper presents an end-to-end deep learning method to solve geometry problems via feature learning and contrastive learning of multimodal data.A key challenge in solving geometry problems using deep learning is to automatically adapt to the task of understanding single-modal and multimodal problems.Existing methods either focus on single-modal ormultimodal problems,and they cannot fit each other.A general geometry problem solver shouldobviouslybe able toprocess variousmodalproblems at the same time.Inthispaper,a shared feature-learning model of multimodal data is adopted to learn the unified feature representation of text and image,which can solve the heterogeneity issue between multimodal geometry problems.A contrastive learning model of multimodal data enhances the semantic relevance betweenmultimodal features and maps them into a unified semantic space,which can effectively adapt to both single-modal and multimodal downstream tasks.Based on the feature extraction and fusion of multimodal data,a proposed geometry problem solver uses relation extraction,theorem reasoning,and problem solving to present solutions in a readable way.Experimental results show the effectiveness of the method. 展开更多
关键词 Geometry problems multimodal feature learning multimodal contrastive learning automatic solver
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Two-Dimensional Riemann Problems:Transonic Shock Waves and Free Boundary Problems
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作者 Gui-Qiang G.Chen 《Communications on Applied Mathematics and Computation》 2023年第3期1015-1052,共38页
We are concerned with global solutions of multidimensional(M-D)Riemann problems for nonlinear hyperbolic systems of conservation laws,focusing on their global configurations and structures.We present some recent devel... We are concerned with global solutions of multidimensional(M-D)Riemann problems for nonlinear hyperbolic systems of conservation laws,focusing on their global configurations and structures.We present some recent developments in the rigorous analysis of two-dimensional(2-D)Riemann problems involving transonic shock waves through several prototypes of hyperbolic systems of conservation laws and discuss some further M-D Riemann problems and related problems for nonlinear partial differential equations.In particular,we present four different 2-D Riemann problems through these prototypes of hyperbolic systems and show how these Riemann problems can be reformulated/solved as free boundary problems with transonic shock waves as free boundaries for the corresponding nonlinear conservation laws of mixed elliptic-hyperbolic type and related nonlinear partial differential equations. 展开更多
关键词 Riemann problems Two-dimensional(2-D) Transonic shocks Solution structure Free boundary problems Mixed elliptic-hyperbolic type Global configurations Large-time asymptotics Global attractors Multidimensional(M-D) Shock capturing methods
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Solving Algebraic Problems with Geometry Diagrams Using Syntax-Semantics Diagram Understanding
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作者 Litian Huang Xinguo Yu +1 位作者 Lei Niu Zihan Feng 《Computers, Materials & Continua》 SCIE EI 2023年第10期517-539,共23页
Solving Algebraic Problems with Geometry Diagrams(APGDs)poses a significant challenge in artificial intelligence due to the complex and diverse geometric relations among geometric objects.Problems typically involve bo... Solving Algebraic Problems with Geometry Diagrams(APGDs)poses a significant challenge in artificial intelligence due to the complex and diverse geometric relations among geometric objects.Problems typically involve both textual descriptions and geometry diagrams,requiring a joint understanding of these modalities.Although considerable progress has been made in solving math word problems,research on solving APGDs still cannot discover implicit geometry knowledge for solving APGDs,which limits their ability to effectively solve problems.In this study,a systematic and modular three-phase scheme is proposed to design an algorithm for solving APGDs that involve textual and diagrammatic information.The three-phase scheme begins with the application of the statetransformer paradigm,modeling the problem-solving process and effectively representing the intermediate states and transformations during the process.Next,a generalized APGD-solving approach is introduced to effectively extract geometric knowledge from the problem’s textual descriptions and diagrams.Finally,a specific algorithm is designed focusing on diagram understanding,which utilizes the vectorized syntax-semantics model to extract basic geometric relations from the diagram.A method for generating derived relations,which are essential for solving APGDs,is also introduced.Experiments on real-world datasets,including geometry calculation problems and shaded area problems,demonstrate that the proposed diagram understanding method significantly improves problem-solving accuracy compared to methods relying solely on simple diagram parsing. 展开更多
关键词 Algebraic problems with geometry diagrams problem-solving geometry diagram understanding state-transformer paradigm syntax-semantics model
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THE REGULARIZED SOLUTION APPROXIMATION OF FORWARD/BACKWARD PROBLEMS FOR A FRACTIONAL PSEUDO-PARABOLIC EQUATION WITH RANDOM NOISE
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作者 狄华斐 容伟杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期324-348,共25页
This paper deals with the forward and backward problems for the nonlinear fractional pseudo-parabolic equation ut+(-Δ)^(s1)ut+β(-Δ)^(s2)u=F(u,x,t)subject o random Gaussian white noise for initial and final data.Und... This paper deals with the forward and backward problems for the nonlinear fractional pseudo-parabolic equation ut+(-Δ)^(s1)ut+β(-Δ)^(s2)u=F(u,x,t)subject o random Gaussian white noise for initial and final data.Under the suitable assumptions s1,s2andβ,we first show the ill-posedness of mild solutions for forward and backward problems in the sense of Hadamard,which are mainly driven by random noise.Moreover,we propose the Fourier truncation method for stabilizing the above ill-posed problems.We derive an error estimate between the exact solution and its regularized solution in an E‖·‖Hs22norm,and give some numerical examples illustrating the effect of above method. 展开更多
关键词 regularized solution approximation forward/backward problems fractional Laplacian Gaussian white noise Fourier truncation method
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An Effective Hybridization of Quantum-based Avian Navigation and Bonobo Optimizers to Solve Numerical and Mechanical Engineering Problems
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作者 Mohammad H.Nadimi-Shahraki 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第3期1361-1385,共25页
Hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Naviga... Hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Navigation Optimizer Algorithm (QANA) is a recent metaheuristic algorithm inspired by the navigation behavior of migratory birds. Different experimental results show that QANA is a competitive and applicable algorithm in different optimization fields. However, it suffers from shortcomings such as low solution quality and premature convergence when tackling some complex problems. Therefore, instead of proposing a new algorithm to solve these weaknesses, we use the advantages of the bonobo optimizer to improve global search capability and mitigate premature convergence of the original QANA. The effectiveness of the proposed Hybrid Quantum-based Avian Navigation Optimizer Algorithm (HQANA) is assessed on 29 test functions of the CEC 2018 benchmark test suite with different dimensions, 30, 50, and 100. The results are then statistically investigated by the Friedman test and compared with the results of eight well-known optimization algorithms, including PSO, KH, GWO, WOA, CSA, HOA, BO, and QANA. Ultimately, five constrained engineering optimization problems from the latest test suite, CEC 2020 are used to assess the applicability of HQANA to solve complex real-world engineering optimization problems. The experimental and statistical findings prove that the proposed HQANA algorithm is superior to the comparative algorithms. 展开更多
关键词 Optimization Metaheuristic algorithms Evolutionary algorithm Quantum-based avian navigation optimizer algorithm Engineering optimization problems Bionic algorithm
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Existing Problems and Countermeasures of Rural Industry Development in Bijie Experimental Area
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作者 Chengdong WANG Xi CHEN +1 位作者 Qin GE Li XIAO 《Asian Agricultural Research》 2023年第11期27-30,34,共5页
The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industri... The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industrial scale,standardization,branding,and marketization,and strives to extend the industrial chain and enhance the value chain to achieve the prosperity of rural industries.In this study,it investigated the current situation of rural industry development in Bijie City(improving the quality and efficiency of characteristic industries,expanding the quantity and efficiency of agricultural products processing industry,recruiting and cultivating large business entities,expanding and strengthening the brand of agricultural products,and upgrading the rural tourism).Through analysis,it found that there are problems such as small scale of production enterprises,insufficient cultivation of independent brands,short industrial chain,low added value,weak market expansion ability,imperfect interest connection mechanism,and insufficient participation of farmers.Finally,it came up with countermeasures for the development of rural industries in Bijie City,including improving supporting facilities and building an extension base;strengthening leading enterprises and focus on deep processing;highlighting regional characteristics and paying close attention to the docking of production and marketing;enhancing the characteristic brand and strengthening the support of science and technology;promoting collaboration and support,and making innovation in the connection of interests. 展开更多
关键词 Rural industries Current development situation problems COUNTERMEASURES Bijie Experimental Area
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Problems of Hazardous Waste Storage Facilities in Coal-fired Power Plants and Countermeasures
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作者 Wenqi YUE 《Meteorological and Environmental Research》 CAS 2023年第2期57-60,65,共5页
The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The enviro... The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems. 展开更多
关键词 Coal-fired power plants Hazardous waste storage Types of problems COUNTERMEASURES
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Construction of Legal System of China's Farmland Protection under the Coexistence of Multiple Objectives:Historical Logic,Practical Problems and Optimization Paths
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作者 Shengnan MA Jiaxin ZHOU Yongfang YANG 《Asian Agricultural Research》 2023年第2期26-34,38,共10页
[Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's r... [Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's reform and opening up,reveal the problems and deep-seated reasons of its legislation,clarify the direction of farmland protection in the new period,and solve the"non-agricultural""non-grain"and ecological problems of farmland.[Methods]Literature analysis and inductive deduction methods were used.[Results]The evolution of the farmland protection legal system has gone through the process of"national consciousness-policy guidelines-institutional system",the change from"single subject to multiple subjects";change from the use of"one-way administrative means to coordinated use of administrative,economic and technical means".The practical problems of the farmland protection legal system are mainly due to the insufficient systematization of the farmland protection legal system itself,the generalization of quantity protection,the transformation of quality protection,and the absence of ecological protection.[Conclusions]It is recommended to improve the existing farmland protection legal system from the establishment of the Farmland Protection Law,the improvement of the farmland protection public participation mechanism and supervision mechanism,the establishment of the farmland quality construction and improvement system,the differentiated farmland occupation and supplementation balance system,and the ecological restoration system. 展开更多
关键词 Farmland protection Legal system construction Policy evolution Existing problems Optimization path
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The coupled deep neural networks for coupling of the Stokes and Darcy–Forchheimer problems
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作者 岳靖 李剑 +1 位作者 张文 陈掌星 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期123-136,共14页
We present an efficient deep learning method called coupled deep neural networks(CDNNs) for coupling of the Stokes and Darcy–Forchheimer problems. Our method compiles the interface conditions of the coupled problems ... We present an efficient deep learning method called coupled deep neural networks(CDNNs) for coupling of the Stokes and Darcy–Forchheimer problems. Our method compiles the interface conditions of the coupled problems into the networks properly and can be served as an efficient alternative to the complex coupled problems. To impose energy conservation constraints, the CDNNs utilize simple fully connected layers and a custom loss function to perform the model training process as well as the physical property of the exact solution. The approach can be beneficial for the following reasons: Firstly, we sample randomly and only input spatial coordinates without being restricted by the nature of samples.Secondly, our method is meshfree, which makes it more efficient than the traditional methods. Finally, the method is parallel and can solve multiple variables independently at the same time. We present the theoretical results to guarantee the convergence of the loss function and the convergence of the neural networks to the exact solution. Some numerical experiments are performed and discussed to demonstrate performance of the proposed method. 展开更多
关键词 scientific computing machine learning the Stokes equations Darcy–Forchheimer problems Beavers–Joseph–Saffman interface condition
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