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Framework for the Structural Analysis of Fractional Differential Equations via Optimized Model Reduction
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作者 Inga Telksniene Tadas Telksnys +3 位作者 Romas Marcinkevicius Zenonas Navickas Raimondas Ciegis Minvydas Ragulskis 《Computer Modeling in Engineering & Sciences》 2025年第11期2131-2156,共26页
Fractional differential equations(FDEs)provide a powerful tool for modeling systems with memory and non-local effects,but understanding their underlying structure remains a significant challenge.While numerous numeric... Fractional differential equations(FDEs)provide a powerful tool for modeling systems with memory and non-local effects,but understanding their underlying structure remains a significant challenge.While numerous numerical and semi-analytical methods exist to find solutions,new approaches are needed to analyze the intrinsic properties of the FDEs themselves.This paper introduces a novel computational framework for the structural analysis of FDEs involving iterated Caputo derivatives.The methodology is based on a transformation that recasts the original FDE into an equivalent higher-order form,represented as the sum of a closed-form,integer-order component G(y)and a residual fractional power seriesΨ(x).This transformed FDE is subsequently reduced to a first-order ordinary differential equation(ODE).The primary novelty of the proposed methodology lies in treating the structure of the integer-order component G(y)not as fixed,but as a parameterizable polynomial whose coefficients can be determined via global optimization.Using particle swarm optimization,the framework identifies an optimal ODE architecture by minimizing a dual objective that balances solution accuracy against a high-fidelity reference and the magnitude of the truncated residual series.The effectiveness of the approach is demonstrated on both a linear FDE and a nonlinear fractional Riccati equation.Results demonstrate that the framework successfully identifies an optimal,low-degree polynomial ODE architecture that is not necessarily identical to the forcing function of the original FDE.This work provides a new tool for analyzing the underlying structure of FDEs and gaining deeper insights into the interplay between local and non-local dynamics in fractional systems. 展开更多
关键词 Fractional differential equations Caputo derivative fractional power series ordinary differential equation model reduction structural optimization particle swarm optimization
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Factors in Work-Related Musculoskeletal Disorders in Dentists:A Structural Equation Model
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作者 Shunhang Li Jian Li +6 位作者 Xin Xu Yushan Huang Yilin Zhang Xiaoshuang Xu Weizhen Guan Xiaoping Liu Jing Li 《Biomedical and Environmental Sciences》 2025年第5期639-643,共5页
Dentistry is a profession with a high prevalence of work-related musculoskeletal disorders(WMSDs),with symptoms often appearing very early in one’s career[1].WMSDs are conditions affecting the muscles,bones,and nervo... Dentistry is a profession with a high prevalence of work-related musculoskeletal disorders(WMSDs),with symptoms often appearing very early in one’s career[1].WMSDs are conditions affecting the muscles,bones,and nervous system due to occupational factors.In 2002,the International Labor Organization included musculoskeletal diseases in the International List of Occupational Diseases.China’s recently updated Classification and Catalog of Occupational Diseases has introduced two new categories of occupational illnesses,including occupational musculoskeletal disorders.WMSDs significantly impact the health and work of dentists,reducing their quality of life and causing economic losses.These disorders are multifactorial in nature,influenced by personal,psychosocial,biomechanical,and environmental factors.Dentists frequently maintain static or awkward postures during procedures,which leads to musculoskeletal strain and discomfort;additionally,long working hours contribute to psychological stress,further increasing the risk of WMSDs[2]. 展开更多
关键词 DENTISTS occupational factors classification catalog occupational diseases musculoskeletal disorders wmsds awkward postures work related musculoskeletal disorders structural equation model static postures
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Investigation of the role of personal factors on work injury in underground mines using structural equation modeling 被引量:5
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作者 P.S.Paul 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期815-819,共5页
Work injuries in mines are complex and generally characterized by several factors starting from personal to technical and technical to social characteristics.In this paper,investigation was made through the applicatio... Work injuries in mines are complex and generally characterized by several factors starting from personal to technical and technical to social characteristics.In this paper,investigation was made through the application of structural equation modeling to study the nature of relationships between the influencing/associating personal factors and work injury and their sequential relationships leading towards work injury occurrences in underground coal mines.Six variables namely,rebelliousness,negative affectivity,job boredom,job dissatisfaction and work injury were considered in this study.Instruments were developed to quantify them through a questionnaire survey.Underground mine workers were randomly selected for the survey.Responses from 300 participants were used for the analysis.The structural model of LISREL was used to estimate the interrelationships amongst the variables.The case study results show that negative affectivity and job boredom induce more job dissatisfaction to the workers whereas risk taking attitude of the individual is positively influenced by job dissatisfaction as well as by rebelliousness characteristics of the individual.Finally,risk taking and job dissatisfaction are having positive significant direct relationship with work injury.The findings of this study clearly reveal that rebelliousness,negative affectivity and job boredom are the three key personal factors influencing work related injuries in mines that need to be addressed properly through effective safety programs. 展开更多
关键词 structural equation modeling Mine safety Occupational health and safety Work injury
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Factors influencing the internet banking adoption decision in North Cyprus: an evidence from the partial least square approach of the structural equation modeling 被引量:2
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作者 Hiba Alhassany Faisal Faisal 《Financial Innovation》 2018年第1期422-442,共21页
Purpose:This paper aims to examine how the adoption decision of the internet banking in North Cyprus would be affected based on the following dimensions;the technology features,the personal characteristics,the social ... Purpose:This paper aims to examine how the adoption decision of the internet banking in North Cyprus would be affected based on the following dimensions;the technology features,the personal characteristics,the social environment and the expected risk.Design/methodology/approach:A self-administered survey was conducted with 291 participants responded to it.The partial least square approach of the structural equation modeling(PLS-SEM)is employed to investigate the direct effects of the proposed factors on the adoption decision.Additionally,the mediation test is used to examine indirect effects.Findings:Results showed that even though the participants appreciated the benefits of the online banking as the perceived usefulness factor exerts the greatest direct effect,they would rather use clear and easy-to-use websites,adding to that their assessments of the usefulness of these services are significantly influenced by the surrounding people’s views and prior experience.This is demonstrated by the total effects of the perceived ease of use and the subjective norm factors,which are greater than the direct effect of the perceived usefulness factor since both of these factors have significant direct and indirect effects mediated by the perceived usefulness factor.The negative impact of the perceived risk factor is weak compared to the previous factors.While the personal innovativeness factor showed the weakest effect among the proposed factors. 展开更多
关键词 Behavioral theories Technology adoption TAM Subjective norm Personal innovativeness Perceived risk Partial least square structural equation modeling
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Structural equation modeling analysis of factors influencing architects' trust in project design teams 被引量:1
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作者 丁志坤 NG Fung-fai 《Journal of Chongqing University》 CAS 2009年第1期32-36,共5页
This paper describes a structural equation modeling (SEM) analysis of factors influencing architects' trust in project design teams. We undertook a survey of architects, during which we distributed 193 questionnair... This paper describes a structural equation modeling (SEM) analysis of factors influencing architects' trust in project design teams. We undertook a survey of architects, during which we distributed 193 questionnaires in 29 A-level architectural design institutes selected radomly from the altogether 59 ones in Shenzhen, P. R. China, and received 130 valid questionnaires. We used Amos 6.0 for SEM to identify significant personal construct based factors affecting interpersonal trust. The results show that only social interaction between architects significantly affects their interpersonal trust. The explained variance of trus~ is not very high in the model. Therefore, future research should add more factors into the current model. The practical implication is that team managers should promote the social interactions between team members such that the interpersonal trust level between team members can be improved. 展开更多
关键词 architect trust project design team cluster sampling structural equation modeling
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Application of Structural Equation Modeling to Evaluate Service Quality of Sportswear Retailing 被引量:1
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作者 李敏 顾彤宇 +1 位作者 杨以雄 洪涛敏 《Journal of Donghua University(English Edition)》 EI CAS 2008年第1期6-10,共5页
Structural Equation Modeling (SEM) used widely in sociology, economics and psychology is adopted. Based on data obtained from marketing research, and using statistical analysis software SPSSll. 0 and LISRELS. 7, The... Structural Equation Modeling (SEM) used widely in sociology, economics and psychology is adopted. Based on data obtained from marketing research, and using statistical analysis software SPSSll. 0 and LISRELS. 7, Theory of Five Dimensions of service quality is proved to be suitable in sportswear retailing in China. It analyzes the relationship among five dimensions and puts them in order of importance as to service quality in sportswear retailing. Advices are given for sportswear retail companies to improve their .Service quality and enhance customer loyalty. 展开更多
关键词 service quality Theory of Five Dimensions SPORTSWEAR structural equation modeling (SEM)
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Functional generalized estimating equation model to detect glaucomatous visual field progression
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作者 Sanghun Jeong Hwayeong Kim +4 位作者 Sangwoo Moon EunAh Kim Hojin Yang Jiwoong Lee Kouros Nouri-Mahdavi 《International Journal of Ophthalmology(English edition)》 2026年第2期302-311,共10页
AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:... AIM:To build a functional generalized estimating equation(GEE)model to detect glaucomatous visual field progression and compare the performance of the proposed method with that of commonly employed algorithms.METHODS:Totally 716 eyes of 716 patients with primary open angle glaucoma(POAG)with at least 5 reliable 24-2 test results and 2y of follow-up were selected.The functional GEE model was used to detect perimetric progression in the training dataset(501 eyes).In the testing dataset(215 eyes),progression was evaluated the functional GEE model,mean deviation(MD)and visual field index(VFI)rates of change,Advanced Glaucoma Intervention Study(AGIS)and Collaborative Initial Glaucoma Treatment Study(CIGTS)scores,and pointwise linear regression(PLR).RESULTS:The proposed method showed the highest proportion of eyes detected as progression(54.4%),followed by the VFI rate(34.4%),PLR(23.3%),and MD rate(21.4%).The CIGTS and AGIS scores had a lower proportion of eyes detected as progression(7.9%and 5.1%,respectively).The time to detection of progression was significantly shorter for the proposed method than that of other algorithms(adjusted P≤0.019).The VFI rate displayed moderate pairwise agreement with the proposed method(k=0.47).CONCLUSION:The functional GEE model shows the highest proportion of eyes detected as perimetric progression and the shortest time to detect perimetric progression in patients with POAG. 展开更多
关键词 functional generalized estimating equation model primary open angle glaucoma perimetric progression
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The Interaction Mechanism Between Urban Scale Hierarchy and Urban Networks in China:An Analysis Based on A Spatial Simultaneous Equation Model
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作者 ZHOU Ying ZHENG Wensheng WANG Xiaofang 《Chinese Geographical Science》 2026年第1期19-33,共15页
Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefor... Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development. 展开更多
关键词 urban scale hierarchy urban networks spatial interaction spatial spillover effect Baidu migration data spatial simultaneous equation model China
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Linking Structural Equation Modeling with Bayesian Network and Its Application to Coastal Phytoplankton Dynamics in the Bohai Bay
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作者 XU Xiao-fu SUN Jian +2 位作者 NIE Hong-tao YUAN De-kui TAO Jian-hua 《China Ocean Engineering》 SCIE EI CSCD 2016年第5期733-748,共16页
Bayesian networks (BN) have many advantages over other methods in ecological modeling, and have become an increasingly popular modeling tool. However, BN are flawed in regard to building models based on inadequate e... Bayesian networks (BN) have many advantages over other methods in ecological modeling, and have become an increasingly popular modeling tool. However, BN are flawed in regard to building models based on inadequate existing knowledge. To overcome this limitation, we propose a new method that links BN with structural equation modeling (SEM). In this method, SEM is used to improve the model structure for BN. This method was used to simulate coastal phytoplankton dynamics in the Bohai Bay. We demonstrate that this hybrid approach minimizes the need for expert elicitation, generates more reasonable structures for BN models, and increases the BN model's accuracy and reliability. These results suggest that the inclusion of SEM for testing and verifying the theoretical structure during the initial construction stage improves the effectiveness of BN models, especially for complex eco-environment systems. The results also demonstrate that in the Bohai Bay, while phytoplankton biomass has the greatest influence on phytoplankton dynamics, the impact of nutrients on phytoplankton dynamics is larger than the influence of the physical environment in summer. Furthermore, although the Redfield ratio indicates that phosphorus should be the primary nutrient limiting factor, our results show that silicate plays the most important role in regulating phytoplankton dynamics in the Bohai Bay. 展开更多
关键词 structural equation modeling Bayesian networks ecological modeling Bohai Bay phytoplankton dynamics
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Analysis of Satisfaction with Business Cost in Shanghai Using Structural Equation Modeling Approach
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作者 郭彦 孙明贵 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期688-694,共7页
Tracing the origins of business cost, to define the satisfaction assessment factors on the business cost in Shanghai was investigated in this paper. Arguing that these effects: a single low cost is not only the criter... Tracing the origins of business cost, to define the satisfaction assessment factors on the business cost in Shanghai was investigated in this paper. Arguing that these effects: a single low cost is not only the criterion determining satisfaction. Other important factors, such as enterprise internal cognitive attitude,stability of the external environment,the quality of perceptions of government services can affect satisfaction. Within structural equation modeling( SEM) approach, six sets of hypotheses are drawn up and tested with a sample of 338 enterprises using questionnaires. Additionally,the analyses of findings introduce the crucial importance of these features in the assessment of satisfaction with business cost in Shanghai. Finally, the results show that internal cognitive has a positive impact on satisfaction. Stability of the external environment has a significant relationship with the effectiveness of government services. Stability of the external environmeat and the effectiveness of government servises have a positive effect on satisfaction. 展开更多
关键词 business cost structural equation modeling(SEM) SATISFACTION
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Validation of general linear modeling for identifying factors associated with Quality of Life: A comparison with structural equation modeling
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作者 Naoko Kumagai Motonori Hatta +1 位作者 Yashiyasu Okuhara Hideki Origasa 《Health》 2013年第11期1884-1888,共5页
Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model inc... Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model including factors that are associated with the sub-domain. However, using the summation score ignores the influence of individual questions. Structural equation modeling (SEM) can account for the influence of each question’s score by compositing a latent variable from each question of a sub-domain. The objective of this study is to determine whether a conventional approach such as GLM, with its use of the summation score, is valid from the standpoint of the SEM approach. Method: We used the Japanese version of the Maugeri Foundation Respiratory Failure Questionnaire, a QOL measure, on 94 patients with heart failure. The daily activity sub-domain of the questionnaire was selected together with its four accompanying factors, namely, living together, occupation, gender, and the New York Heart Association’s cardiac function scale (NYHA). The association level between individual factors and the daily activity sub-domain was estimated using SEM?and GLM, respectively. The standard partial regression coefficients of GLM and standardized path coefficients of SEM were compared. If?these coefficients were similar (absolute value of the difference -0.06 and -0.07 for the GLM and SEM. Likewise, the estimates of occupation, gender, and NYHA were -0.18 and -0.20, -0.08 and -0.08, 0.51 and 0.54, respectively. The absolute values of the difference for each factor were 0.01, 0.02, 0.00, and 0.03, respectively. All differences were less than 0.05. This means that these two approaches lead to similar conclusions. Conclusion: GLM is a valid method for exploring association factors with a domain in QOL. 展开更多
关键词 General LINER modeling LATENT Variable Standardized Path COEFFICIENT Standard Partial Regression COEFFICIENT structural equation modeling
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Factors Affecting Quality of Equipment Maintenance Based on Structural Equation Modeling
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作者 解永芬 张桦 支丹 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期292-295,共4页
Factors affecting equipment maintenance quality usually include personnel,equipment and facilities,raw materials and spare parts, craft, environment and quality management. These six factors affecting maintenance qual... Factors affecting equipment maintenance quality usually include personnel,equipment and facilities,raw materials and spare parts, craft, environment and quality management. These six factors affecting maintenance quality are not all the same degree. In order to find out which factor can influence equipment maintenance quality greatly and achieve sophisticated management,characteristic quantities of six factors are presented. A structural equation modeling( SEM) is designed using the six factors as latent variables and their characteristic quantities as the observed variable.According to the basic data obtained from the questionnaire survey,calculate the standardized regression weight by parameter estimation of the SEM. Then the key factors affecting the quality of the equipment maintenance are determined with the help of the standardized regression weight. 展开更多
关键词 equipment maintenance structural equation modeling(SEM) affecting factors
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Mechanisms Influencing Learning Gains Under Information Security: Structural Equation Modeling with Mediating Effect
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作者 Teng Zong Fengsi Wang +1 位作者 Xin Wei Yibo Liu 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3447-3468,共22页
With the expanding enrollments in higher education,the quality of col-lege education and the learning gains of students have attracted much attention.It is important to study the influencing factors and mechanisms of ... With the expanding enrollments in higher education,the quality of col-lege education and the learning gains of students have attracted much attention.It is important to study the influencing factors and mechanisms of individual stu-dents’acquisition of learning gains to improve the quality of talent cultivation in colleges.However,in the context of information security,the original data of learning situation surveys in various universities involve the security of educa-tional evaluation data and daily privacy of teachers and students.To protect the original data,data feature mining and correlation analyses were performed at the model level.This study selected 12,181 pieces of data from X University,which participated in the Chinese College Student Survey(CCSS)from 2018 to 2021.A confirmatory factor analysis was conducted and a structural equation modeling was conducted using AMOS 24.0.Through hypothesis testing,this study explored the mechanisms that influence learning gains from the per-spectives of student involvement,teacher involvement,and school support.The results indicated that the quality of student involvement has an important mediat-ing effect on learning gains and that a supportive campus environment has the greatest influence on learning gains.Establishing positive emotional communica-tions between teachers and students is a more direct and effective method than improving the teaching level to improve the quality of student involvement.This study discusses the implications of these results on the research and practice of connotative development in higher education. 展开更多
关键词 structural equation model mediating effect chinese college student survey learning gains
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Generalized structural equation modeling:Symptom heterogeneity in attention-deficit/hyperactivity disorder leading to poor treatment efficacy
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作者 Ruu-Fen Tzang Yue-Cune Chang 《World Journal of Psychiatry》 SCIE 2022年第6期787-800,共14页
BACKGROUND Treatment efficacy for attention-deficit/hyperactivity disorder(ADHD)is reported to be poor,possibly due to heterogeneity of ADHD symptoms.Little is known about poor treatment efficacy owing to ADHD heterog... BACKGROUND Treatment efficacy for attention-deficit/hyperactivity disorder(ADHD)is reported to be poor,possibly due to heterogeneity of ADHD symptoms.Little is known about poor treatment efficacy owing to ADHD heterogeneity.AIM To use generalized structural equation modeling(GSEM)to show how the heterogeneous nature of hyperactivity/impulsivity(H/I)symptoms in ADHD,irritable oppositional defiant disorder(ODD),and the presentation of aggression in children interferes with treatment responses in ADHD.METHODS A total of 231 children and adolescents completed ADHD inattention and H/I tests.ODD scores from the Swanson,Nolan,and Pelham,version IV scale were obtained.The child behavior checklist(CBCL)and parent’s satisfaction questionnaire were completed.The relationships were analyzed by GSEM.RESULTS GSEM revealed that the chance of ADHD remission was lower in children with a combination of H/I symptoms of ADHD,ODD symptoms,and childhood aggressive behavior.ODD directly mediated ADHD symptom severity.The chance of reaching remission based on H/I symptoms of ADHD was reduced by 13.494%[=exp(2.602)]in children with comorbid ADHD and ODD[odds ratio(OR)=2.602,95%confidence interval(CI):1.832-3.373,P=0.000]after adjusting for the effects of other factors.Childhood aggression mediated ODD symptom severity.The chance of reaching remission based on ODD symptoms was lowered by 11.000%[=1-exp(-0.117)]in children with more severe baseline symptoms of aggression based on the CBCL score at study entry[OR=-0.117,95%CI:(-0.190)-(-0.044),P=0.002].CONCLUSION Mediation through ODD symptoms and aggression may influence treatment effects in ADHD after adjusting for the effects of baseline ADHD symptom severity.More attention could be directed to the early recognition of risks leading to ineffective ADHD treatment,e.g.,symptoms of ODD and the presentation of aggressive or delinquent behaviors and thought problems in children with ADHD. 展开更多
关键词 Attention-deficit/hyperactivity disorder Oppositional defiant disorder AGGRESSION REMISSION Generalized structural equation modeling
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Meta-analytic structural equation modeling:a primer
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作者 Zhen-Wei Dai 《Medical Data Mining》 2022年第2期36-42,共7页
Meta-analytic structural equation modeling is a new research field which can help to explain the relationship between a group of variables in several studies by testing structural equation modeling.However,this method... Meta-analytic structural equation modeling is a new research field which can help to explain the relationship between a group of variables in several studies by testing structural equation modeling.However,this methodology is still not very popular in many countries and researchers due to lack of promotion.This report aim s to giv e a primer on the principle of m eta-analytic structural equation modeling and provid e a reference for subsequent researchers to conduct m eta-analytic structural equation modeling analysis. 展开更多
关键词 meta analysis structural equation modeling meta-analytic structural equation modeling social science PSYCHOLOGY
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A Survey Study on TPACK Framework for Normal Students of English Major in Ethnic Colleges and Universities:Empirical Analysis Based on Structural Equation Modeling
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作者 Qinxian Chen Xuanxuan Zhong Xinyi Liu 《Journal of Contemporary Educational Research》 2024年第9期112-119,共8页
With the continuous advancement of education informatization,Technological Pedagogical Content Knowledge(TPACK),as a new theoretical framework,provides a novel method for measuring teachers’informatization teaching a... With the continuous advancement of education informatization,Technological Pedagogical Content Knowledge(TPACK),as a new theoretical framework,provides a novel method for measuring teachers’informatization teaching ability.This study takes normal students of English majors from three ethnic universities as the research object,collects relevant data through questionnaires,and uses structural equation modeling to conduct data analysis and empirical research to investigate the differences in the TPACK levels of these students at different grades and the structural relationships among the elements in the TPACK structure.The technological pedagogical knowledge element of the TPACK structure was not obtained by exploratory factors analysis but through path analysis and structural equation modeling,the results show that the one-dimensional core knowledge of technological knowledge(TK),content knowledge(CK),and pedagogical knowledge(PK)have a positive effect on the two-dimensional interaction knowledge of technological content knowledge(TCK)and pedagogical content knowledge(PCK);furthermore,TCK and PCK have a positive effect on TPACK;and TK,CK,and PK indirectly affect TPACK through TCK and PCK.On this basis,suggestions are provided to ethnic colleges and universities to develop the TPACK knowledge competence of normal students of English majors. 展开更多
关键词 TPACK Ethnic colleges and universities Normal students of English major structural equation modeling
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Accuracy Comparison of Data Imputation Estimation Using Structural Equation Modeling Between Constrained and Unconstrained Approaches
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作者 Narong Phothi Somchai Prakancharoen 《通讯和计算机(中英文版)》 2012年第3期297-302,共6页
关键词 结构方程模型 测量精度 M估计 矿产资源 归责 美国加州大学 测试数据 网上数据库
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Porosity prediction based on improved structural modeling deep learning method guided by petrophysical information
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作者 Bo-Cheng Tao Huai-Lai Zhou +3 位作者 Wen-Yue Wu Gan Zhang Bing Liu Xing-Ye Liu 《Petroleum Science》 2025年第6期2325-2338,共14页
Porosity is an important attribute for evaluating the petrophysical properties of reservoirs, and has guiding significance for the exploration and development of oil and gas. The seismic inversion is a key method for ... Porosity is an important attribute for evaluating the petrophysical properties of reservoirs, and has guiding significance for the exploration and development of oil and gas. The seismic inversion is a key method for comprehensively obtaining the porosity. Deep learning methods provide an intelligent approach to suppress the ambiguity of the conventional inversion method. However, under the trace-bytrace inversion strategy, there is a lack of constraints from geological structural information, resulting in poor lateral continuity of prediction results. In addition, the heterogeneity and the sedimentary variability of subsurface media also lead to uncertainty in intelligent prediction. To achieve fine prediction of porosity, we consider the lateral continuity and variability and propose an improved structural modeling deep learning porosity prediction method. First, we combine well data, waveform attributes, and structural information as constraints to model geophysical parameters, constructing a high-quality training dataset with sedimentary facies-controlled significance. Subsequently, we introduce a gated axial attention mechanism to enhance the features of dataset and design a bidirectional closed-loop network system constrained by inversion and forward processes. The constraint coefficient is adaptively adjusted by the petrophysical information contained between the porosity and impedance in the study area. We demonstrate the effectiveness of the adaptive coefficient through numerical experiments.Finally, we compare the performance differences between the proposed method and conventional deep learning methods using data from two study areas. The proposed method achieves better consistency with the logging porosity, demonstrating the superiority of the proposed method. 展开更多
关键词 Porosity prediction Deep learning Improved structural modeling Petrophysical information
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Computational Modeling of Streptococcus Suis Dynamics via Stochastic Delay Differential Equations
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作者 Umar Shafique Ali Raza +4 位作者 Dumitru Baleanu Khadija Nasir Muhammad Naveed Abu Bakar Siddique Emad Fadhal 《Computer Modeling in Engineering & Sciences》 2025年第4期449-476,共28页
Streptococcus suis(S.suis)is a major disease impacting pig farming globally.It can also be transferred to humans by eating raw pork.A comprehensive study was recently carried out to determine the indices throughmultip... Streptococcus suis(S.suis)is a major disease impacting pig farming globally.It can also be transferred to humans by eating raw pork.A comprehensive study was recently carried out to determine the indices throughmultiple geographic regions in China.Methods:The well-posed theorems were employed to conduct a thorough analysis of the model’s feasible features,including positivity,boundedness equilibria,reproduction number,and parameter sensitivity.Stochastic Euler,Runge Kutta,and EulerMaruyama are some of the numerical techniques used to replicate the behavior of the streptococcus suis infection in the pig population.However,the dynamic qualities of the suggested model cannot be restored using these techniques.Results:For the stochastic delay differential equations of the model,the non-standard finite difference approach in the sense of stochasticity is developed to avoid several problems such as negativity,unboundedness,inconsistency,and instability of the findings.Results from traditional stochastic methods either converge conditionally or diverge over time.The stochastic non-negative step size convergence nonstandard finite difference(NSFD)method unconditionally converges to the model’s true states.Conclusions:This study improves our understanding of the dynamics of streptococcus suis infection using versions of stochastic with delay approaches and opens up new avenues for the study of cognitive processes and neuronal analysis.Theplotted interaction behaviour and new solution comparison profiles. 展开更多
关键词 Streptococcus suis disease model stochastic delay differential equations(SDDEs) existence and uniqueness Lyapunov function stability results reproduction number computational methods
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Coupling Relationship Analysis on Households′ Production Behaviors and Their Influencing Factors in Nature Reserves:A Structural Equation Model 被引量:6
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作者 WANG Changhai WEN Yali +1 位作者 DUAN Wei HAN Feng 《Chinese Geographical Science》 SCIE CSCD 2013年第4期506-518,共13页
A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by inter... A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by interrelated factors,such as protection attitudes,resource endowment,and family wealth.This research evaluated households near the Crested Ibis National Nature Reserve in Shaanxi Province,acquiring data from 436 households around Yang County and Ningshan County in the south slope of Qinling Mountains,China.Based on the collected data,we developed a structural equation model to evaluate the coupling relationships among households′ protection attitudes,production behaviors,resource endowment,and family wealth.The results showed that:1) households with great resource endowment had more negative attitudes,probably due to their greater protection costs;2) the households with higher education levels had worse protection attitudes;3) the households with more family wealth were likely to use fewer fertilizers,pesticides,and firewood;4) the households with more resource endowment showed less production and management behaviors;5) the enhancement of households' attitudes improved production behaviors to protection the environment,but the effects were not statistically significant.Our results provide a basis for the government's protection policy making,exploring the effective management measures that are beneficial for both nature reserve management and community development. 展开更多
关键词 family wealth protection attitudes production behaviors resource endowment structural equation model Crested Ibis National Nature Reserve
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