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Research and Practice of the Blended Teaching Model of BOPPPS Teaching Method Under the Background of Digital Education: Taking Operations Research Course as an Example
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作者 Yan Wu 《Journal of Contemporary Educational Research》 2024年第6期155-160,共6页
The rapid development of digital education provides new opportunities and challenges for teaching model innovation.This study aims to explore the application of the BOPPPS(Bridge-in,Objective,Pre-assessment,Participat... The rapid development of digital education provides new opportunities and challenges for teaching model innovation.This study aims to explore the application of the BOPPPS(Bridge-in,Objective,Pre-assessment,Participatory learning,Post-assessment,Summary)teaching method in the development of a blended teaching model for the Operations Research course under the background of digital education.In response to the characteristics of the course and the needs of the student group,the teaching design is reconstructed with a student-centered approach,increasing practical teaching links,improving the assessment and evaluation system,and effectively implementing it in conjunction with digital educational technology.This teaching model has shown significant effectiveness in the context of digital education,providing valuable experience and insights for the innovation of the Operations Research course. 展开更多
关键词 Digital education BOPPPS teaching method Blended teaching model Operations research
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The Dilemma of the Times and the Remolding of the Way of Model Education
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作者 Xiaojuan Wang 《Journal of Contemporary Educational Research》 2020年第9期56-59,共4页
As a general method of ideological and political education,model education has played an irreplaceable role in Chinese history.But in this pluralistic social background,it has been questioned and misinterpreted by mor... As a general method of ideological and political education,model education has played an irreplaceable role in Chinese history.But in this pluralistic social background,it has been questioned and misinterpreted by more and more people,and the role model of traditional model education is gradually weakening.Model Education contributes to the construction of a harmonious socialist society and is an important channel to promote the all-round development of human beings and realize the harmony of interpersonal relations.Combing the theory of model education,endowing it with new connotation of the times,analyzing the situation of the current development and reshaping the new educational path,it plays an inestimable role in the development of individuals and society,it also contributes to the innovation of ideological and political education methods and provides a reference for the overall development of model education. 展开更多
关键词 Model education Method DILEMMA Path reshaping
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A Study on the Evaluation Method and Evaluation Model of the Effectiveness of Consumer Financial Education
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作者 FANG Yun CHEN ying Yerzhigit Khalikova 《International English Education Research》 2017年第2期25-28,共4页
With the understanding of the importance of financial education and research, the study of the effectiveness of financial education is more and more, but there have been debate on the effectiveness of financial educat... With the understanding of the importance of financial education and research, the study of the effectiveness of financial education is more and more, but there have been debate on the effectiveness of financial education and education costs. This paper summarizes and classifies the methods and models to improve the effective research of financial education, including improving the effectiveness of financial education and improving the effectiveness of financial education through the design of different educational methods. The guiding principles of the evaluation of the effectiveness of financial consumer education proposed by the International Financial Consumers' Education Network (INFE) and the guidance of our government on the evaluation of the effectiveness of financial education. 展开更多
关键词 Consumer The Effectiveness of Financial education Evaluation Method Evaluation Model
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Trend surface analysis of forest landscape pattern in Guandishan forest region of Shanxi,China 被引量:3
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作者 Guo Jin-ping Xiao Yang +1 位作者 Zhang Yun-xiang Xiao Du-ning 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第2期73-79,共7页
Landscape pattern is a widely used concept for the demonstration of landscape characteristic features. The integral spatial distribution trend of landscape elements is interested point in the landscape ecological rese... Landscape pattern is a widely used concept for the demonstration of landscape characteristic features. The integral spatial distribution trend of landscape elements is interested point in the landscape ecological research, especially in those of complex secondary forest regions with confusing mosaics of land cover. Trend surface analysis which used in community and population ecological researches was introduced to reveal the landscape pattern. A reasonable and reliable approach for application of trend surface analysis was provided in detail. As key steps of the approach, uniform grid point sampling method was developed. The efforts were also concentrated at an example of Guandishan forested landscape. Some basic rules of spatial distribution of landscape elements were exclaimed. These will be benefit to the further study in the area to enhance the forest sustainable management and landscape planning. 展开更多
关键词 landscape pattern trend surface model uniform grid point sampling method forest landscape spatial distribution.
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Numerical prediction of inner turbulent flow in conical diffuser by using a new five-point scheme and DLR k-ε turbulence model 被引量:2
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作者 蒋光彪 何永森 +1 位作者 舒适 肖映雄 《Journal of Central South University》 SCIE EI CAS 2008年第S1期181-186,共6页
The internal turbulent flow in conical diffuser is a very complicated adverse pressure gradient flow.DLR k-ε turbulence model was adopted to study it.The every terms of the Laplace operator in DLR k-ε turbulence mod... The internal turbulent flow in conical diffuser is a very complicated adverse pressure gradient flow.DLR k-ε turbulence model was adopted to study it.The every terms of the Laplace operator in DLR k-ε turbulence model and pressure Poisson equation were discretized by upwind difference scheme.A new full implicit difference scheme of 5-point was constructed by using finite volume method and finite difference method.A large sparse matrix with five diagonals was formed and was stored by three arrays of one dimension in a compressed mode.General iterative methods do not work wel1 with large sparse matrix.With algebraic multigrid method(AMG),linear algebraic system of equations was solved and the precision was set at 10-6.The computation results were compared with the experimental results.The results show that the computation results have a good agreement with the experiment data.The precision of computational results and numerical simulation efficiency are greatly improved. 展开更多
关键词 conical DIFFUSER turbulent flow DLR k-ε turbulence model 5-point scheme ALGEBRAIC MULTIGRID method(AMG)
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Proximal Point-Like Method for Updating Simultaneously Mass and Stiffness Matrices of Finite Element Model
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作者 DAI Hua WANG Kangkang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第1期1-12,共12页
The problem of correcting simultaneously mass and stiffness matrices of finite element model of undamped structural systems using vibration tests is considered in this paper.The desired matrix properties,including sat... The problem of correcting simultaneously mass and stiffness matrices of finite element model of undamped structural systems using vibration tests is considered in this paper.The desired matrix properties,including satisfaction of the characteristic equation,symmetry,positive semidefiniteness and sparsity,are imposed as side constraints to form the optimal matrix pencil approximation problem.Using partial Lagrangian multipliers,we transform the nonlinearly constrained optimization problem into an equivalent matrix linear variational inequality,develop a proximal point-like method for solving the matrix linear variational inequality,and analyze its global convergence.Numerical results are included to illustrate the performance and application of the proposed method. 展开更多
关键词 model updating proximal point method optimal matrix pencil approximation matrix linear variational inequality
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A Fluid-Structure Interaction Simulation of Coal and Gas Outbursts Based on the Interaction between the Gas Pressure and Deformation of a Coal-Rock Mass
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作者 Lin Fang Mengjun Wu +3 位作者 Bin Wu Honglin Li Chenhao He Fan Sun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1649-1668,共20页
Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium,the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a flu... Based on the theories of the gas seepage in coal seams and the deformation of the coal-rock medium,the gas seepage field in coal-rock mass is coupled with the deformation field of the coal-rock mass to establish a fluidstructure interaction model for the interaction between coal gas and coal-rock masses.The outburst process in coal-rock masses under the joint action of gas pressure and crustal stress is simulated using the material point method.The simulation results show the changes in gas pressure,velocity distribution,maximum principal stress distribution,and damage distribution during the process of the coal and gas outburst,as well as themovement and accumulation of coal-rock masses after the occurrence of the outburst.It was found that the gas pressure gradient was greatest at theworking face after the occurrence of the outburst,the gas pressures and pressure gradients at each location within the coal seamgradually decreased with time,and the damage distribution was essentially the same as the minimum principal stress distribution.The simulation further revealed that the outburst first occurred in themiddle of the tunnel excavation face and that the speed at which particles of coal mass were ejected was highest at the center and decreased toward the upper and lower sides.The study provides a scientific basis for enhancing our understanding of the mechanism behind coal and gas outbursts,as well as their prevention and control. 展开更多
关键词 Coal and gas outburst fluid-structure interaction model material point method numerical simulation
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Semantic model and optimization of creative processes at mathematical knowledge formation
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 The Cybernetic Conception Optimization of CONTROL Quantitative and Qualitative Information Measures Modelling Intellectual Systems Neural Network MATHEMATICAL education The CONTROL of Pedagogical PROCESSES CREATIVE Pedagogics Cognitive and CREATIVE PROCESSES Informal Axiomatic Thery SEMANTIC NET NET Optimization Parameters The Topology of SEMANTIC NET Metrization The System of Coverings Stochastic Model of CREATIVE PROCESSES At The Formation of MATHEMATICAL Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of The CREATIVE PROCESSES CONTROL Interdisciplinary Learning: Colorimetric Barycenter
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Empirical Research on the Relationship between Education Poverty Alleviation and Rural Revitalization—Spatial Panel Simultaneous Equation Model Based on Provincial Panel Data
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作者 Ningning Li Shichang Shen 《Open Journal of Applied Sciences》 2023年第11期2032-2046,共15页
On the basis of using entropy weight method to measure China’s education poverty alleviation and rural revitalization evaluation indicators, using the panel data of 30 provinces in China (excluding Xizang, Hong Kong,... On the basis of using entropy weight method to measure China’s education poverty alleviation and rural revitalization evaluation indicators, using the panel data of 30 provinces in China (excluding Xizang, Hong Kong, Macao and Taiwan) from 2012 to 2021, a spatial panel simultaneous equation model is constructed based on adjacency matrix, geographical distance matrix and economic geographical distance matrix deeply study the interaction mechanism and spatial spillover effects between education poverty alleviation and rural revitalization through the generalized spatial three-stage least squares method (GS3SLS). The results indicate that there is a significant spatial spillover effect and a positive spatial correlation between education poverty alleviation and rural revitalization, and there is a significant interactive effect between the two variables, while promoting each other positively. Therefore, the government should clarify the deep relationship between education poverty alleviation and rural revitalization based on the current background, and better consolidate and expand the effective connection between the achievements of education poverty alleviation and rural revitalization. 展开更多
关键词 education Poverty Alleviation Rural Revitalization Entropy Weight Method Space Panel Simultaneous Equation Model GS3SLS
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An Efficient Reliability-Based Optimization Method Utilizing High-Dimensional Model Representation and Weight-Point Estimation Method
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作者 Xiaoyi Wang Xinyue Chang +2 位作者 Wenxuan Wang Zijie Qiao Feng Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1775-1796,共22页
The objective of reliability-based design optimization(RBDO)is to minimize the optimization objective while satisfying the corresponding reliability requirements.However,the nested loop characteristic reduces the effi... The objective of reliability-based design optimization(RBDO)is to minimize the optimization objective while satisfying the corresponding reliability requirements.However,the nested loop characteristic reduces the efficiency of RBDO algorithm,which hinders their application to high-dimensional engineering problems.To address these issues,this paper proposes an efficient decoupled RBDO method combining high dimensional model representation(HDMR)and the weight-point estimation method(WPEM).First,we decouple the RBDO model using HDMR and WPEM.Second,Lagrange interpolation is used to approximate a univariate function.Finally,based on the results of the first two steps,the original nested loop reliability optimization model is completely transformed into a deterministic design optimization model that can be solved by a series of mature constrained optimization methods without any additional calculations.Two numerical examples of a planar 10-bar structure and an aviation hydraulic piping system with 28 design variables are analyzed to illustrate the performance and practicability of the proposed method. 展开更多
关键词 Reliability-based design optimization high-dimensional model decomposition point estimation method Lagrange interpolation aviation hydraulic piping system
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Application of Weighted Average Method in Evaluation System for Rural Cadre Distance Education
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作者 DAI Li-na1,ZHENG Bo-wei1,DONG Hai-ge2 1.Institute of Agricultural Scientech Information,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China 2.Food Quality Supervision and Management Section,Chaoyang Branch of Beijing Administration for Industry and Commerce,Beijing 100125,China 《Asian Agricultural Research》 2012年第3期66-68,共3页
We elaborate the application method,process and effect of weighted average method in the examination and evaluation system for modern distance education of rural party members and cadres.The study shows that this meth... We elaborate the application method,process and effect of weighted average method in the examination and evaluation system for modern distance education of rural party members and cadres.The study shows that this method reflects the evaluation results objectively and comprehensively and plays a remarkable role in establishing and improving the examination and evaluation system,thus will have an important reference value for the development of modern distance education of rural party members and cadres in the future. 展开更多
关键词 RURAL MODERN distance education WEIGHTED AVERAGE m
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Study on the Prediction of Rice Blast Based on the Unbiased GM (1,1) Model 被引量:1
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作者 魏代俊 曾艳敏 邹迎春 《Plant Diseases and Pests》 CAS 2010年第6期4-6,共3页
To create a new prediction model, the unbiased GM (1,1) model is optimized by the five-point slide method in this paper. Then, based on the occurrence areas of dce blast in Enshi District during 1995 -2004, the new ... To create a new prediction model, the unbiased GM (1,1) model is optimized by the five-point slide method in this paper. Then, based on the occurrence areas of dce blast in Enshi District during 1995 -2004, the new model and unbiased GM (1, 1 ) model are applied to predict the occurrence areas of rice blast during 2005 -2010. Predicting outcomes show that the prediction accuracy of five-point unbiased sliding optimized GM (1, 1 ) model is higher than the unbiased GM (1,1) model. Finally, combined with the prediction results, the author provides some suggestion for Enshi District in the prevention and control of rice blast in 2010. 展开更多
关键词 Unbiased GM (1 1 model Five-point slide method Optimization PREDICTION Rice blast
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具有投放的周期系数Schoner生态模型的极限性态
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作者 陆忠华 陈菊芳 《陕西师大学报(自然科学版)》 CSCD 1995年第3期18-22,共5页
讨论了具有投放率的周期系数Schoner生态模型,运用Brouwer不动点定理、凹算子和解算子最终收敛于不动点的方法,得到正周期解的存在性和唯一性及全局渐近稳定性的充分条件.
关键词 生态模型 周期解 全局稳定性 微分方程
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Stability of a Delayed SIQRS Model with Temporary Immunity 被引量:2
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作者 Laid Chahrazed Rahmani Fouad Lazhar 《Advances in Pure Mathematics》 2013年第2期240-245,共6页
This paper addresses a time-delayed SIQRS model with a linear incidence rate. Immunity gained by experiencing the disease is temporary;whenever infected, the disease individuals will return to the susceptible class af... This paper addresses a time-delayed SIQRS model with a linear incidence rate. Immunity gained by experiencing the disease is temporary;whenever infected, the disease individuals will return to the susceptible class after a fixed period of time. First, the local and global stabilities of the infection-free equilibrium are analyzed, respectively. Second, the endemic equilibrium is formulated in terms of the incidence rate, and locally asymptotic stability. Finally we use the adomian decomposition method is applied to the system epidemiologic. This method yields an analytical solution in terms of convergent infinite power series. 展开更多
关键词 Adomian Method EPIDEMIOLOGY Mathematical MODEL The EPIDEMIC MODEL The EQUILIBRIUM POINTS
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Dynamical Behaviors of Nonlinear Coronavirus (COVID-19) Model with Numerical Studies 被引量:3
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作者 Khaled A.Gepreel Mohamed S.Mohamed +1 位作者 Hammad Alotaibi Amr M.S.Mahdy 《Computers, Materials & Continua》 SCIE EI 2021年第4期675-686,共12页
The development of mathematical modeling of infectious diseases is a key research area in various elds including ecology and epidemiology.One aim of these models is to understand the dynamics of behavior in infectious... The development of mathematical modeling of infectious diseases is a key research area in various elds including ecology and epidemiology.One aim of these models is to understand the dynamics of behavior in infectious diseases.For the new strain of coronavirus(COVID-19),there is no vaccine to protect people and to prevent its spread so far.Instead,control strategies associated with health care,such as social distancing,quarantine,travel restrictions,can be adopted to control the pandemic of COVID-19.This article sheds light on the dynamical behaviors of nonlinear COVID-19 models based on two methods:the homotopy perturbation method(HPM)and the modied reduced differential transform method(MRDTM).We invoke a novel signal ow graph that is used to describe the COVID-19 model.Through our mathematical studies,it is revealed that social distancing between potentially infected individuals who are carrying the virus and healthy individuals can decrease or interrupt the spread of the virus.The numerical simulation results are in reasonable agreement with the study predictions.The free equilibrium and stability point for the COVID-19 model are investigated.Also,the existence of a uniformly stable solution is proved. 展开更多
关键词 Nonlinear COVID-19 model equilibrium point stability existence of uniformly stable signal ow graph homotopy perturbation method reduced differential transform method
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Modeling footing resting on anisotropic sand using material point method 被引量:1
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作者 Liu Gao Dong Liao Pin-Qiang Mo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3271-3290,共20页
Sand typically exhibits anisotropic internal structure which may significantly influence its mechanical behavior. The material point method (MPM) can eliminate mesh distortion and thus is suitable for investigating ge... Sand typically exhibits anisotropic internal structure which may significantly influence its mechanical behavior. The material point method (MPM) can eliminate mesh distortion and thus is suitable for investigating geotechnical problems with large deformation. In this study, an advanced anisotropic critical state theory (ACST)-based soil model is implemented in MPM to study the response of strip footing resting on anisotropic sand. The capability of the model is verified by simulating several element tests and strip footing tests with different soil densities and fabric bedding plane orientations. For the footing problem with a vertical load, as the fabric bedding plane orientation increases, the bearing capacity decreases and its corresponding settlement increases. The failure pattern becomes asymmetrical when the bedding plane orientation or the loading direction is inclined. A comparison between the simulation results predicted by the anisotropic and isotropic models is made, which demonstrates that neglecting the fabric anisotropy may lead to the overestimation of the bearing capacity. 展开更多
关键词 Material point method(MPM) FOOTING Constitutive model ANISOTROPY Inclined loading
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An Algorithm for Determination of Projectile Attitude Angles in Projectile Trajectory Prediction
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作者 Zha Qicheng Rui Xiaoting +1 位作者 Yu Hailong Zhou Qinbo 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期361-370,共10页
A fast and accurate algorithm is established in this paper to increase the precision of ballistic trajectory prediction.The algorithm is based on the six-degree-of-freedom(6 DOF)trajectory equations,to estimate the pr... A fast and accurate algorithm is established in this paper to increase the precision of ballistic trajectory prediction.The algorithm is based on the six-degree-of-freedom(6 DOF)trajectory equations,to estimate the projectile attitude angles in every measuring time.Hereby,the algorithm utilizes the Davidon-Fletcher-Powell(DFP)method to solve nonlinear equations and Doppler radar trajectory test information containing only position coordinates of the projectile to reconstruct the angular information.The″position coordinates by the test″and″angular displacements by reconstruction″at the end phase of the radar measurement are used as an initial value for the trajectory computation to extrapolate the trajectory impact point.The numerical simulations validate the proposed method and demonstrate that the estimated impact point agrees very well with the real one.Morover,other artillery trajectory can be predicted by the algorithm,and other trajectory models,such as 4 DOF and 5 DOF models,can also be incorporated into the proposed algorithm. 展开更多
关键词 ballistic TRAJECTORY impact point prediction Davidon-Fletcher-Powell method six-degree-of-freedom TRAJECTORY model Doppler radar data
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Sensitivity analysis of composite laminated plates with bonding imperfection in Hamilton system
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作者 李顶河 徐建新 卿光辉 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第12期1549-1560,共12页
Sensitivity analysis of composite laminated plates with bonding imperfection is carried out based on the radial point interpolation method (RPIM) in a Hamilton system. A set of hybrid governing equations of response... Sensitivity analysis of composite laminated plates with bonding imperfection is carried out based on the radial point interpolation method (RPIM) in a Hamilton system. A set of hybrid governing equations of response and sensitivity quantities is reduced using the spring-layer model and the modified Hellinger-Reissner (H-R) variational principle. The analytical method (AM), the semi-analytical method (SAM), and the finite difference method (FDM) are used for sensitivity analysis based on the reduced set of hybrid governing equations. A major advantage of the hybrid governing equations is that the convolution algorithm is avoided in sensitivity analysis. In addition, sensitivity analysis using this set of hybrid governing equations can obtain response values and sensitivity coefficients simultaneously, and accounts for bonding imperfection of composite laminated plates. 展开更多
关键词 bonding imperfection sensitivity analysis radial point interpolation method(RPIM) spring-layer model Hellinger-Reissner (H-R) variational principle
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Hydraulics Management Model of Response Function Solved by Laplace Transform Boundary Element Method
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作者 尹尚先 孟召平 +1 位作者 刘月琴 王磊 《International Journal of Mining Science and Technology》 2000年第2期95-98,共4页
In solving a response function by the boundary element method, the use of the singular valued method and the Laplace transform in a time domain makes the solving process be simplified and the result be accurate. The r... In solving a response function by the boundary element method, the use of the singular valued method and the Laplace transform in a time domain makes the solving process be simplified and the result be accurate. The restricted condition matrix formed by the response matrix method is much smaller than that by embedding method. In addition, the response function may realize directly the management decision making. So it is efficient for establishing and solving hydraulics management models. 展开更多
关键词 BEM response matrix method hydraulics management model aplace transform singular points
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Relation between viscoplastic flow, periodic feature and Joule heat validity for electrically assisted friction stir welding
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作者 Geng Haibin Luo Jian +1 位作者 Gao Jianjun Xiang Junfeng 《China Welding》 CAS 2020年第4期33-40,共8页
Electrically assisted friction stir welding is a promising way to improve liquidity of viscoplastic metal. However, this local heat source only can take into effect in a certain contact interface status. Semi-analytic... Electrically assisted friction stir welding is a promising way to improve liquidity of viscoplastic metal. However, this local heat source only can take into effect in a certain contact interface status. Semi-analytical model and FEM are adopted to analyze materials flow in electrically assisted FSW. Semi-analysis results show that Joule heating is validity with rotation speed 1 400 r/min and travel speed 400 mm/min. The maximum flow velocity is 0.033 m/s when travel speed is 400 mm/min, and it increases to 0.043 m/s with current assistant. Visco-plasticizing efficiency is a key factor to decide whether Joule heat is significant, and viscoplastic flow can periodically make circuit short. Periodic torque, axial force and onion rings surface show dynamic flow process, which can be used to illustrate the dynamic contact resistance feature and correct the calculation equation of Joule heat. This paper is aim to point out the potential relation between viscoplastic flow, periodic torque and Joule heating validity. 展开更多
关键词 Electrically assisted friction stir welding dynamic contact resistance visco-plasticizing efficiency semi-analytical model point tracing method
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