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Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis
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作者 Zhi-Wei Fu Yue-Jing Li +3 位作者 Ran Yu Rui-Qing Guo Li-Xia Gao Sheng-Xia Zhao 《World Journal of Psychiatry》 SCIE 2025年第1期128-136,共9页
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu... BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children. 展开更多
关键词 Preschool children Parenting stress Children's behavioral and emotional problems Family rearing Mediating effect
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Efficacy of School-Based Interventions to Manage Psychosocial Problems of an Adolescent: A Clinical Case Study
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作者 Dua Fatima Afzaal Farhan Hashmi 《Open Journal of Medical Psychology》 2025年第1期19-31,共13页
This case study explores the efficacy of school-based intervention to address psychosocial challenges faced by an 11-year-old adolescent. The case study aimed to decrease the agression and acting out behavior as resul... This case study explores the efficacy of school-based intervention to address psychosocial challenges faced by an 11-year-old adolescent. The case study aimed to decrease the agression and acting out behavior as result of being victimized at school by the peers. The aim was to assess and manage the child’s aggressive behavior and academic underperformance which played a significant role in the child’s low self-esteem and emotional regulation. A comprehensive assessment was conducted to rule out the difficulties and a multi-faceted intervention strategy was utilized including anger management and structured activity scheduling that helped that child to improve his academic performance as well as to learn to manage his emotional expression. Throughout 16 sessions, the intervention targeted key behavioural indicators such as emotional expression, and aggression;post-assessment results demonstrated a 22% improvement in the child’s behavioral and academic challenges. The findings suggest that a multi-faceted therapeutic approach can be effective in addressing complex issues of aggression and academic underperformance in children, highlighting the importance of integrated psychological and educational interventions. 展开更多
关键词 AGGRESSION School-Related problems BULLYING VICTIMIZATION Cognitive-Behavioral Therapy
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An Initial-Boundary Value Problem for a Modified Transitional Korteweg-de Vries Equation
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作者 Charles Bu 《Journal of Applied Mathematics and Physics》 2025年第1期138-147,共10页
We study the following modified transitional Korteweg-de Vries equation ut+f(t)upux+uxxx=0, (x,t)∈R+×R+, (p≥2is an even integer) with initial value u(x,0)=g(x)∈H4(R+)and inhomogeneous boundary value u(0,t)=Q(t... We study the following modified transitional Korteweg-de Vries equation ut+f(t)upux+uxxx=0, (x,t)∈R+×R+, (p≥2is an even integer) with initial value u(x,0)=g(x)∈H4(R+)and inhomogeneous boundary value u(0,t)=Q(t)∈C2([ 0,∞ )). Under the conditions either (i) f(t)≤0, f′(t)≥0or (ii) f(t)≤−αwhere α>0, we prove the existence of a unique global classical solution. 展开更多
关键词 Modified Transitional KdV Equation Initial-Boundary Value problem Semi-Group Local and Global Existence
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Fekete-SzegöInequalities and the Symmetric Toeplitz Determinants for Certain Analytic Function Class Involving q-Differintegral Operator
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作者 PEI Ke-ke LONG Pin-hong +1 位作者 LIU Jin-lin GANGADHARAN Murugusundaramoorthy 《Chinese Quarterly Journal of Mathematics》 2024年第4期366-378,共13页
In this paper,we introduce and investigate certain subclass of analytic and univalent functions involving q-differintegral operator.For this function class,we give the bound estimates of the coefficients a2 and a3 and... In this paper,we introduce and investigate certain subclass of analytic and univalent functions involving q-differintegral operator.For this function class,we give the bound estimates of the coefficients a2 and a3 and some Fekete-Szegöfunctional inequalities.Besides,we also estimate the corresponding symmetric Toeplitz determinants.Furthermore,we point out some consequences and connections to these results above. 展开更多
关键词 fekete-szegöproblem Symmetric Toeplitz determinant Analytic function q-differintegral operator
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两类双单叶Bazilevic函数类的Fekete-Szegö不等式
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作者 张亚 《宁德师范学院学报(自然科学版)》 2024年第1期4-9,共6页
在两类双单叶Bazilevic函数类的引入应用下,采用分析技巧研究Fekete-Szegö不等式.在完成f(x)∈M^(uλ)_(Σ)(ϕ)、f(x)∈H_(Σ)(u,λ,k)两类双单叶定义定理分析后探讨推论结果,所获取的第三项系数估计实现了对部分双单叶函数已有结... 在两类双单叶Bazilevic函数类的引入应用下,采用分析技巧研究Fekete-Szegö不等式.在完成f(x)∈M^(uλ)_(Σ)(ϕ)、f(x)∈H_(Σ)(u,λ,k)两类双单叶定义定理分析后探讨推论结果,所获取的第三项系数估计实现了对部分双单叶函数已有结果的改进. 展开更多
关键词 两类双单叶 Bazilevic函数类 fekete-szegö不等式
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On the Fekete-Szeg5 Problem for a Class of Analytic Functions 被引量:4
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作者 郭栋 李宗涛 黄金超 《Chinese Quarterly Journal of Mathematics》 2015年第3期442-449,共8页
The Fekete-Szego inequality for a subclass H(α,λ,A,B) of the class H of normalized analytic functions is studied.For each f(z)=z+~∞∑_(n=2)αnz^n ∈ H(α,λ,A,B),the sharp upper bounds of |α_3-α_2~2|for any compl... The Fekete-Szego inequality for a subclass H(α,λ,A,B) of the class H of normalized analytic functions is studied.For each f(z)=z+~∞∑_(n=2)αnz^n ∈ H(α,λ,A,B),the sharp upper bounds of |α_3-α_2~2|for any complex parameter u are obtained by using the fundamental inequalities of analytic functions and analytical techniques and the applications of the inequality of functions defined with Hadaniard product are proved. 展开更多
关键词 UNIVALENT FUNCTION H(α λ A B) FUNCTION fekete-szeg5 INEQUALITY
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THE FEKETE-SZEG PROBLEM FOR CLOSE-TO-CONVEX FUNCTIONS WITH RESPECT TO THE KOEBE FUNCTION 被引量:1
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作者 Bogumila KOWALCZYK Adam LECKO 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1571-1583,共13页
An analytic function f in the unit disk D := {z ∈ C : |z| 〈 1}, standardly normalized, is called close-to-convex with respect to the Koebe function k(z) := z/(1-z)2, z ∈ D, if there exists δ ∈ (-π/2,... An analytic function f in the unit disk D := {z ∈ C : |z| 〈 1}, standardly normalized, is called close-to-convex with respect to the Koebe function k(z) := z/(1-z)2, z ∈ D, if there exists δ ∈ (-π/2,π/2) such that Re {eiδ(1-z)2f′(z)} 〉 0, z ∈ D. For the class C(k) of all close-to-convex functions with respect to k, related to the class of functions convex in the positive direction of the imaginary axis, the Fekete-Szego problem is studied. 展开更多
关键词 fekete-szego problem close-to-convex functions close-to-convex functionswith respect to the Koebe function close-to-convex functions with argumentδ functions convex in the positive direction of the imaginary axis
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Fekete-Szego Problem for a Subclass of Meromorphic Functions Defined by the Dziok-Srivastava Operator
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作者 Guo Dong Li Zong-tao Xiong Liang-peng 《Communications in Mathematical Research》 CSCD 2018年第2期184-192,共9页
By using the hypergeometric function defined by the Dziok-Srivastava operator, a new subclass of meromorphic function is introdued. We obtain Fekete-Szeg? inequalities for the meromorphic function f(z) for which α-(1... By using the hypergeometric function defined by the Dziok-Srivastava operator, a new subclass of meromorphic function is introdued. We obtain Fekete-Szeg? inequalities for the meromorphic function f(z) for which α-(1 + α{1 +z[_lI_mf(z)]′′/[_lI_mf(z)]′}/z[_lI_mf(z)]′/_lI_mf(z))■φ(z)(α ∈ C-{1/2, 1}). 展开更多
关键词 analytic and meromorphic function starlike and convex function hypergeometric function fekete-szeg? problem Dziok-Srivastava operator Hadamard product
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Majorization and Fekete-Szegö Problems for Multivalent Meromorphic Functions Associated with the Mittag-Leffler Function
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作者 LONG Pin-hong GANGADHARAN Murugusundaramoorthy +1 位作者 HAN Hui-li WANG Wen-shuai 《Chinese Quarterly Journal of Mathematics》 2022年第2期111-123,共13页
The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclas... The main object of this present paper is to investigate the problem of majorization of certain class of multivalent meromorphic functions of complex order involving Mittag-Leffler function. Meanwhile, for this subclass the corresponding coefficient estimates and some Fekete-Szegö type inequalities are obtained. Moreover we point out some new or known consequences of our main results. 展开更多
关键词 Meromorphic function Majorization problem Hadamard product(convolution) Mittag-Leer function fekete-szegöinequality
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Association of preschool children behavior and emotional problems with the parenting behavior of both parents 被引量:3
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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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Quafu-Qcover:Explore combinatorial optimization problems on cloud-based quantum computers 被引量:1
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作者 许宏泽 庄伟峰 +29 位作者 王正安 黄凯旋 时运豪 马卫国 李天铭 陈驰通 许凯 冯玉龙 刘培 陈墨 李尚书 杨智鹏 钱辰 靳羽欣 马运恒 肖骁 钱鹏 顾炎武 柴绪丹 普亚南 张翼鹏 魏世杰 增进峰 李行 龙桂鲁 金贻荣 于海峰 范桁 刘东 胡孟军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期104-115,共12页
We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and c... We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight graph.The core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA circuit.Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers.Compared to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed performance.Additionally,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum devices.This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity.The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous processing.Moreover,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization problems.We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers. 展开更多
关键词 quantum cloud platform combinatorial optimization problems quantum software
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Data-Driven Learning Control Algorithms for Unachievable Tracking Problems 被引量:1
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作者 Zeyi Zhang Hao Jiang +1 位作者 Dong Shen Samer S.Saab 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期205-218,共14页
For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to in... For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best approximation.Subsequently, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete information.To address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain design.The input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings. 展开更多
关键词 Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems
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Fekete-Szego Problem for Certain Subclass ofp-Valent Analytic Functions usingQuasi-Subordination
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作者 AO En LI Shu-hai +1 位作者 TANG Huo Siqinqimuge 《Chinese Quarterly Journal of Mathematics》 2017年第4期432-440,共9页
In this paper, a new certain class of р-valent analytic functions with quasisubordination is defined and the Fekete-Szeg? problems for functions belonging to the class are derived. The results presented here provide ... In this paper, a new certain class of р-valent analytic functions with quasisubordination is defined and the Fekete-Szeg? problems for functions belonging to the class are derived. The results presented here provide extensions of those given in some earlier works. 展开更多
关键词 analytic functions р-valent functions quasi-subordination fekete-szego problem
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An Improved Artificial Rabbits Optimization Algorithm with Chaotic Local Search and Opposition-Based Learning for Engineering Problems and Its Applications in Breast Cancer Problem 被引量:1
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作者 Feyza AltunbeyÖzbay ErdalÖzbay Farhad Soleimanian Gharehchopogh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1067-1110,共44页
Artificial rabbits optimization(ARO)is a recently proposed biology-based optimization algorithm inspired by the detour foraging and random hiding behavior of rabbits in nature.However,for solving optimization problems... Artificial rabbits optimization(ARO)is a recently proposed biology-based optimization algorithm inspired by the detour foraging and random hiding behavior of rabbits in nature.However,for solving optimization problems,the ARO algorithm shows slow convergence speed and can fall into local minima.To overcome these drawbacks,this paper proposes chaotic opposition-based learning ARO(COARO),an improved version of the ARO algorithm that incorporates opposition-based learning(OBL)and chaotic local search(CLS)techniques.By adding OBL to ARO,the convergence speed of the algorithm increases and it explores the search space better.Chaotic maps in CLS provide rapid convergence by scanning the search space efficiently,since their ergodicity and non-repetitive properties.The proposed COARO algorithm has been tested using thirty-three distinct benchmark functions.The outcomes have been compared with the most recent optimization algorithms.Additionally,the COARO algorithm’s problem-solving capabilities have been evaluated using six different engineering design problems and compared with various other algorithms.This study also introduces a binary variant of the continuous COARO algorithm,named BCOARO.The performance of BCOARO was evaluated on the breast cancer dataset.The effectiveness of BCOARO has been compared with different feature selection algorithms.The proposed BCOARO outperforms alternative algorithms,according to the findings obtained for real applications in terms of accuracy performance,and fitness value.Extensive experiments show that the COARO and BCOARO algorithms achieve promising results compared to other metaheuristic algorithms. 展开更多
关键词 Artificial rabbit optimization binary optimization breast cancer chaotic local search engineering design problem opposition-based learning
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ON DE FINETTI'S OPTIMAL IMPULSE DIVIDEND CONTROL PROBLEM UNDER CHAPTER 11 BANKRUPTCY 被引量:1
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作者 王文元 明瑞星 胡亦钧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期215-233,共19页
Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the... Motivated by recent advances made in the study of dividend control and risk management problems involving the U.S.bankruptcy code,in this paper we follow[44]to revisit the De Finetti dividend control problem under the reorganization process and the regulator's intervention documented in U.S.Chapter 11 bankruptcy.We do this by further accommodating the fixed transaction costs on dividends to imitate the real-world procedure of dividend payments.Incorporating the fixed transaction costs transforms the targeting optimal dividend problem into an impulse control problem rather than a singular control problem,and hence computations and proofs that are distinct from[44]are needed.To account for the financial stress that is due to the more subtle concept of Chapter 11 bankruptcy,the surplus process after dividends is driven by a piece-wise spectrally negative Lévy process with endogenous regime switching.Some explicit expressions of the expected net present values under a double barrier dividend strategy,new to the literature,are established in terms of scale functions.With the help of these expressions,we are able to characterize the optimal strategy among the set of admissible double barrier dividend strategies.When the tail of the Lévy measure is log-convex,this optimal double barrier dividend strategy is then verified as the optimal dividend strategy,solving our optimal impulse control problem. 展开更多
关键词 spectrally negative Lévy process Chapter 11 bankruptcy De Finetti's dividend problem double barrier strategy impulse control
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Enhancing Critical Path Problem in Neutrosophic Environment Using Python
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作者 M.Navya Pratyusha Ranjan Kumar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2957-2976,共20页
In the real world,one of the most common problems in project management is the unpredictability of resources and timelines.An efficient way to resolve uncertainty problems and overcome such obstacles is through an ext... In the real world,one of the most common problems in project management is the unpredictability of resources and timelines.An efficient way to resolve uncertainty problems and overcome such obstacles is through an extended fuzzy approach,often known as neutrosophic logic.Our rigorous proposed model has led to the creation of an advanced technique for computing the triangular single-valued neutrosophic number.This innovative approach evaluates the inherent uncertainty in project durations of the planning phase,which enhances the potential significance of the decision-making process in the project.Our proposed method,for the first time in the neutrosophic set literature,not only solves existing problems but also introduces a new set of problems not yet explored in previous research.A comparative study using Python programming was conducted to examine the effectiveness of responsive and adaptive planning,as well as their differences from other existing models such as the classical critical path problem and the fuzzy critical path problem.The study highlights the use of neutrosophic logic in handling complex projects by illustrating an innovative dynamic programming framework that is robust and flexible,according to the derived results,and sets the stage for future discussions on its scalability and application across different industries. 展开更多
关键词 Classical critical path problem fuzzy critical path problem uncertainty neutrosophic triangular single-valued neutrosophic number neutrosophic critical path problem python programming languag
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A Comparative Study of Metaheuristic Optimization Algorithms for Solving Real-World Engineering Design Problems
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作者 Elif Varol Altay Osman Altay Yusuf Ovik 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期1039-1094,共56页
Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as ... Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as industry,automotive,construction,machinery,and interdisciplinary research.However,there are established optimization techniques that have shown effectiveness in addressing these types of issues.This research paper gives a comparative study of the implementation of seventeen new metaheuristic methods in order to optimize twelve distinct engineering design issues.The algorithms used in the study are listed as:transient search optimization(TSO),equilibrium optimizer(EO),grey wolf optimizer(GWO),moth-flame optimization(MFO),whale optimization algorithm(WOA),slimemould algorithm(SMA),harris hawks optimization(HHO),chimp optimization algorithm(COA),coot optimization algorithm(COOT),multi-verse optimization(MVO),arithmetic optimization algorithm(AOA),aquila optimizer(AO),sine cosine algorithm(SCA),smell agent optimization(SAO),and seagull optimization algorithm(SOA),pelican optimization algorithm(POA),and coati optimization algorithm(CA).As far as we know,there is no comparative analysis of recent and popular methods against the concrete conditions of real-world engineering problems.Hence,a remarkable research guideline is presented in the study for researchersworking in the fields of engineering and artificial intelligence,especiallywhen applying the optimization methods that have emerged recently.Future research can rely on this work for a literature search on comparisons of metaheuristic optimization methods in real-world problems under similar conditions. 展开更多
关键词 Metaheuristic optimization algorithms real-world engineering design problems multidisciplinary design optimization problems
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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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Efficient Inverse Analysis for Solving a Coupled Conduction,Convection and Radiation Problem Involving Non⁃gray Participating Media
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作者 HE Zheng CAO Zhenkun +2 位作者 CHENG Xiang CUI Miao LIU Kun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第5期621-631,共11页
The presence of non-gray radiative properties in a reheating furnace’s medium that absorbs,emits,and involves non-gray creates more complex radiative heat transfer problems.Furthermore,it adds difficulty to solving t... The presence of non-gray radiative properties in a reheating furnace’s medium that absorbs,emits,and involves non-gray creates more complex radiative heat transfer problems.Furthermore,it adds difficulty to solving the coupled conduction,convection,and radiation problem,leading to suboptimal efficiency that fails to meet real-time control demands.To overcome this difficulty,comparable gray radiative properties of non-gray media are proposed and estimated by solving an inverse problem.However,the required iteration numbers by using a least-squares method are too many and resulted in a very low inverse efficiency.It is necessary to present an efficient method for the equivalence.The Levenberg-Marquardt algorithm is utilized to solve the inverse problem of coupled heat transfer,and the gray-equivalent radiative characteristics are successfully recovered.It is our intention that the issue of low inverse efficiency,which has been observed when the least-squares method is employed,will be resolved.To enhance the performance of the Levenberg-Marquardt algorithm,a modification is implemented for determining the damping factor.Detailed investigations are also conducted to evaluate its accuracy,stability of convergence,efficiency,and robustness of the algorithm.Subsequently,a comparison is made between the results achieved using each method. 展开更多
关键词 inverse problem coupled heat transfer problem Levenberg-Marquardt algorithm
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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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