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Regression analysis and its application to oil and gas exploration:A case study of hydrocarbon loss recovery and porosity prediction,China
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作者 Yang Li Xiaoguang Li +3 位作者 Mingyu Guo Chang Chen Pengbo Ni Zijian Huang 《Energy Geoscience》 EI 2024年第4期240-252,共13页
In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not... In oil and gas exploration,elucidating the complex interdependencies among geological variables is paramount.Our study introduces the application of sophisticated regression analysis method at the forefront,aiming not just at predicting geophysical logging curve values but also innovatively mitigate hydrocarbon depletion observed in geochemical logging.Through a rigorous assessment,we explore the efficacy of eight regression models,bifurcated into linear and nonlinear groups,to accommodate the multifaceted nature of geological datasets.Our linear model suite encompasses the Standard Equation,Ridge Regression,Least Absolute Shrinkage and Selection Operator,and Elastic Net,each presenting distinct advantages.The Standard Equation serves as a foundational benchmark,whereas Ridge Regression implements penalty terms to counteract overfitting,thus bolstering model robustness in the presence of multicollinearity.The Least Absolute Shrinkage and Selection Operator for variable selection functions to streamline models,enhancing their interpretability,while Elastic Net amalgamates the merits of Ridge Regression and Least Absolute Shrinkage and Selection Operator,offering a harmonized solution to model complexity and comprehensibility.On the nonlinear front,Gradient Descent,Kernel Ridge Regression,Support Vector Regression,and Piecewise Function-Fitting methods introduce innovative approaches.Gradient Descent assures computational efficiency in optimizing solutions,Kernel Ridge Regression leverages the kernel trick to navigate nonlinear patterns,and Support Vector Regression is proficient in forecasting extremities,pivotal for exploration risk assessment.The Piecewise Function-Fitting approach,tailored for geological data,facilitates adaptable modeling of variable interrelations,accommodating abrupt data trend shifts.Our analysis identifies Ridge Regression,particularly when augmented by Piecewise Function-Fitting,as superior in recouping hydrocarbon losses,and underscoring its utility in resource quantification refinement.Meanwhile,Kernel Ridge Regression emerges as a noteworthy strategy in ameliorating porosity-logging curve prediction for well A,evidencing its aptness for intricate geological structures.This research attests to the scientific ascendancy and broad-spectrum relevance of these regression techniques over conventional methods while heralding new horizons for their deployment in the oil and gas sector.The insights garnered from these advanced modeling strategies are set to transform geological and engineering practices in hydrocarbon prediction,evaluation,and recovery. 展开更多
关键词 Regression analysis Oil and gas exploration Multiple linear regression model Nonlinear regression model Hydrocarbon loss recovery Porosity prediction
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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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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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Development Status and Countermeasures of Farmers' Professional Cooperatives in Shangqiu City
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作者 Xiaofan XIAO 《Agricultural Biotechnology》 2024年第3期41-44,共4页
Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professiona... Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professional cooperatives in Shangqiu City,this paper expounded the development status of farmers' professional cooperatives in Shangqiu City,analyzed and discussed various problems encountered in the development process of farmers' professional cooperatives,and put forward some countermeasures and suggestions,such as establishing and perfecting cooperative rules and regulations,financing from multiple channels,introducing technical talents in various ways,breaking the information asymmetry restriction by various means,and giving full play to government functions,aiming to further promote standardized,large-scale,healthy and sustainable development of farmers' professional cooperatives. 展开更多
关键词 Farmers'professional cooperatives Shangqiu city Development status Existing problems Countermeasure analysis
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Analysis on the Problems in Start-up and Debugging of Two 600 MW Generating Units in Yangzhou No.2 Thermal Power Plant
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作者 蒯狄正 《Electricity》 2001年第2期11-15,共5页
The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS ... The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS not complying with the contract target, etc. occurred during start-up and debugging of two 600 MW generating units in Yangzhou No.2 Thermal Power Plant. Through analysis on these problems. the remedial measures were put forward, to which can be referred for similar units. 展开更多
关键词 start-up and debugging problems analysis remedial measures 600 MW generating unit
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MIXED ENERGY METHOD FOR SOLUTION OF QUADRATIC PROGRAMMING PROBLEMS AND ELASTIC-PLASTIC ANALYSIS OF TRUSS STRUCTURES 被引量:1
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作者 Zhong Wanxie Zhang Hongwu 《Acta Mechanica Solida Sinica》 SCIE EI 2002年第1期1-8,共8页
A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method propo... A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method proposed is different from the traditionalone, for which the unknown variables are selected just in one classsuch as displacements or stresses. The present method selects thevariables in the mixed form with both displacement and stress. As themethod is established in the hybrid space, the information found inthe previous incremental step can be used for the solution of thepresent step, making the algorithm highly effi- cient in thenumerical solution process of quadratic programming problems. Theresults obtained in the exm- ples of the elastic-plastic solution ofthe truss structures verify what has been predicted in thetheoretical anal- ysis. 展开更多
关键词 elastic-plastic analysis mixed energy method quadratic programming problem
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Existing Problems of Intensive Curing Barn and Optimization Analysis 被引量:1
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作者 左业华 雷庭 +2 位作者 王远辉 刘会忠 卢顺友 《Agricultural Science & Technology》 CAS 2014年第8期1271-1273,共3页
Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update.... Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn. 展开更多
关键词 Intensive curing barn Existing problems Optimization analysis
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Aerial Extent Analysis and Environmental Problems Identification of Matasagar and Sukhsagar Wetlands in Bangladesh Using GIS and Remote Sensing Tools 被引量:1
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作者 Md. Zakiur Rahman Md. Shahedur Rashid 《Journal of Geographic Information System》 2016年第6期683-691,共9页
Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role... Bangladesh is a land of wetlands. Basically, most of them are freshwater wetlands and have great influence on the primary economic activities such as agriculture and fisheries of the country. Due to its important role in the harmonizing ecosystem, wetlands demand much attention as a significant part of our environment. Matasagar and Sukhsagar are very important historical wetlands of Bangladesh. But those are endangered today due to lack of public awareness of the dangers of their activities to the environment and unbridled profit making activities of the commercial users of the wetlands. Comparisons of maps and Google images from 1933 to present have shown that the forest areas of the wetlands have been progressively destroyed, and these have greatly affected the biodiversity of these areas mentioned. GIS (Geographic Information System) and remote sensing techniques are used to identify the changes in the aerial extent of those wetlands. This study also tried to explore present environmental conditions by in-situ observation. This is high time;some serious steps should be taken to ensure the conservation and preservation of these areas mentioned. 展开更多
关键词 Historical Wetland Extent analysis Environment problems GIS Remote Sensing
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Analysis of Problems and Solutions form Three Roles of CALL in Chinese College English Teaching Context
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作者 王巧霞 《海外英语》 2012年第1X期61-61,63,共2页
There is no question that Computer Assisted Language Learning(CALL) has been a feature of teaching and learning in college.CALL plays a significant role in second language teaching.This article will focus on an overvi... There is no question that Computer Assisted Language Learning(CALL) has been a feature of teaching and learning in college.CALL plays a significant role in second language teaching.This article will focus on an overview of three different types of roles of CALL to demonstrate its application in Chinese college English teaching. 展开更多
关键词 analysis of problems solutions THREE ROLES
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Analysis on the Status Quo and Existing Problems of the Longgang River Basin Management
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作者 Chen Chunxing 《Meteorological and Environmental Research》 CAS 2019年第5期117-118,124,共3页
In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are d... In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are discussed.The research aims to provide reference for the management of the Longgang River basin. 展开更多
关键词 The Longgang RIVER BASIN WATER ENVIRonMENT PROBLEM analysis
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Boundary Value Problems for Burgers Equations, through Nonstandard Analysis
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作者 Saida Bendaas 《Applied Mathematics》 2015年第6期1086-1098,共13页
In this paper we study inviscid and viscid Burgers equations with initial conditions in the half plane . First we consider the Burgers equations with initial conditions admitting two and three shocks and use the HOPF-... In this paper we study inviscid and viscid Burgers equations with initial conditions in the half plane . First we consider the Burgers equations with initial conditions admitting two and three shocks and use the HOPF-COLE transformation to linearize the problems and explicitly solve them. Next we study the Burgers equation and solve the initial value problem for it. We study the asymptotic behavior of solutions and we show that the exact solution of boundary value problem for viscid Burgers equation as viscosity parameter is sufficiently small approach the shock type solution of boundary value problem for inviscid Burgers equation. We discuss both confluence and interacting shocks. In this article a new approach has been developed to find the exact solutions. The results are formulated in classical mathematics and proved with infinitesimal technique of non standard analysis. 展开更多
关键词 Non Standard analysis BOUNDARY Value Problem Viscid BURGERS EQUATIon INVISCID BURGERS EQUATIon Heat EQUATIon
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Analysis of Existing Problems and Treatment Methods of Urban Environmental Monitoring
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作者 Zhang Qiandong Song Xin 《Journal of Environmental Science and Engineering(A)》 2022年第2期49-54,共6页
With the rapid development of the city,the concept of ecological environment has been integrated into everyone’s heart.In the new era,people also have higher requirements for the quality of living environment.However... With the rapid development of the city,the concept of ecological environment has been integrated into everyone’s heart.In the new era,people also have higher requirements for the quality of living environment.However,at this stage,with the development of urbanization and industrialization,the problem of environmental pollution has become more and more serious.Therefore,we must do a good job in urban environmental monitoring,pay attention to the protection of urban environment,design and implement effective governance methods,so as to improve the quality of environmental governance.This article analyzes the problems in urban environmental monitoring,and formulates reasonable treatment methods and suggestions. 展开更多
关键词 Urban environmental monitoring problems governance methods analysis
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Explore and Research Forum in Arbitration The New Rules of CIETAC, and its Problems and Development
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作者 Liping Shi 《China's Foreign Trade》 2001年第12期9-14,共6页
Editor’s words The author puts forward some problems involving in CIETAC Arbitration Rules 2000 such as the third nation- ality of the presiding arbitrator, the full autonomy of the parties to choose Arbitration Rule... Editor’s words The author puts forward some problems involving in CIETAC Arbitration Rules 2000 such as the third nation- ality of the presiding arbitrator, the full autonomy of the parties to choose Arbitration Rules and the improvement of applying for interim measures and so on, which are welcomed by CIETAC, though some of which CIETAC does do that in practice, for instance, appointing the third nationalities as presiding arbitrator, and some of which the improvement shall be followed by the law, for instance, the problem of interim measures. We hope there are more articles contributed to arbitration in China directly deal with the theory and practice of arbitration in China as well as all over the world. 展开更多
关键词 explore and Research Forum in Arbitration The New Rules of CIETAC and its problems and Development
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Perturbation Analysis of Structured Least Squares Problems and Its Application in Calibration of Interest Rate Term Structure 被引量:1
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作者 Chen Zhao Weiguo Gao Jungong Xue 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2007年第4期383-392,共10页
A structured perturbation analysis of the least squares problem is considered in this paper.The new error bound proves to be sharper than that for general perturbations. We apply the new error bound to study sensitivi... A structured perturbation analysis of the least squares problem is considered in this paper.The new error bound proves to be sharper than that for general perturbations. We apply the new error bound to study sensitivity of changing the knots for curve fitting of interest rate term structure by cubic spline.Numerical experiments are given to illustrate the sharpness of this bound. 展开更多
关键词 线性函数 最小平方问题 扰动分析 数学分析
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Plights and Outlet:Environmental Problem Analysis of Agricultural Eco-tourism 被引量:2
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作者 廖军华 《Journal of Landscape Research》 2011年第2期84-87,共4页
As agricultural eco-tourism development played a vital role in promoting rural economic and social development and constructing new harmonious countryside,the paper had analyzed environmental problem produced during i... As agricultural eco-tourism development played a vital role in promoting rural economic and social development and constructing new harmonious countryside,the paper had analyzed environmental problem produced during its development,pointed out that blind development of agricultural eco-tourism had seriously destroyed resources and ecological environment and that tourist infrastructure construction and urbanization had ruined rural unique natural landscape.In view of current situation of environment,it also studied reasons causing environmental disruption,which lied in insufficient guidance and support of government,deficient scientific development planning and management system,and poor environmental consciousness of tourist operators and tourists.On this basis,it summarized that agricultural eco-tourism development should follow principles of sustainable development,synchronization between development and protection,and coordination between tourism development and environmental protection.It concluded proper ways to develop agricultural eco-tourism,and emphasized that it should draw up scientific and reasonable development planning,enhance government's macro-administration,establish and perfect ecological compensation mechanism,and strive to cultivate people's environmental awareness. 展开更多
关键词 AGRICULTURAL ECO-TOURISM ENVIRonMENTAL problems analysis Plights OUTLETS
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PERTURBATION ANALYSIS OF A CLASS OF MATRIX INVERSE PROBLEMS
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作者 戴华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期194-198,共5页
A class of matrix inverse problems minimizing ‖A-‖ F on the linear manifold l A={A∈R n×m |‖AX-B‖ F=min} is considered. The perturbation analysis of the solution to these problems is carried out. Th... A class of matrix inverse problems minimizing ‖A-‖ F on the linear manifold l A={A∈R n×m |‖AX-B‖ F=min} is considered. The perturbation analysis of the solution to these problems is carried out. The perturbation upper bounds of the solution are given for both the consistent and inconsistent cases. The obtained preturbation upper bounds are with respect to the distance from the perturbed solution to the unperturbed manifold. 展开更多
关键词 MATRIX inverse problem best approximation perturbation analysis
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Analysis of the Listening Problems in the Interpretation of The Art of Negotiation
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作者 阚淑娟 宫慧英 《疯狂英语(理论版)》 2017年第4期163-164,共2页
The author interpreted the video The Art of Negotiation of Stanford University. In the interpreting process, the interpreter encounters some listening obstacles. Through analyzing the listening problems in the task,th... The author interpreted the video The Art of Negotiation of Stanford University. In the interpreting process, the interpreter encounters some listening obstacles. Through analyzing the listening problems in the task,the author has realized the weakness in interpreting. With the help of the relevance theory,the interpreter comes up with corresponding strategies, gives an analysis of the listening problems encountered in the interpreting process and makes a reflection on the interpreting in order to enhance the interpreting skills. 展开更多
关键词 listening problems analysis relevance theory
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一类非线性非局部抛物问题的类Wilson非协调元分析
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作者 王萍莉 《许昌学院学报》 CAS 2024年第2期1-6,共6页
主要研究在半离散格式下一类非线性非局部抛物问题的类Wilson非协调元逼近.当问题的精确解u∈H^(3)(Ω)时,利用该单元相容误差在能量范数意义下可达到O(h^(2))阶(比其插值误差高一阶)的特殊性质,采用关于时间t的导数转移技巧,并结合双... 主要研究在半离散格式下一类非线性非局部抛物问题的类Wilson非协调元逼近.当问题的精确解u∈H^(3)(Ω)时,利用该单元相容误差在能量范数意义下可达到O(h^(2))阶(比其插值误差高一阶)的特殊性质,采用关于时间t的导数转移技巧,并结合双线性元的高精度分析和插值后处理技巧,得到了超逼近性质和整体超收敛结果. 展开更多
关键词 非线性非局部抛物问题 类Wilson非协调元 高精度分析 超逼近超收敛
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Problem analysis and solutions of the B-ultrasound-guided peripherally inserted central catheter process 被引量:6
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作者 Zu-Yan Fan Tian-Tian Wang +5 位作者 Yun Xiao Yang-En Zhang Dong-Hao Wu Zhi-Huan Lin Dan-Chun Wu Jin-Xiang Lin 《Chinese Nursing Research》 CAS 2016年第3期142-145,共4页
Objective: The purpose of this study was to address the issues that occur during the B-ultrasound guided peripherally inserted central catheter(PICC) process and to give a summary of the effective management to the... Objective: The purpose of this study was to address the issues that occur during the B-ultrasound guided peripherally inserted central catheter(PICC) process and to give a summary of the effective management to these issues accordingly.Methods: The information was collected retrospectively on all of the 1950 PICCs inserted during the 2-year period from July 2013 to July 2015. PICC catheter insertion was performed using the Seldinger approach and was delivered from the basilic vein to the superior vena cava in a B-ultrasound guided manner. Moreover, the point raised during the PICC process would be treated immediately.Results: All of the PICCs were inserted successfully. The problems encountered are shown in the inserted central catheter(PICC) process, such as failures of venipuncture, the problem of inserting guide wire, the catheter was dif?cult to be delivered etc.Conclusions: The B-ultrasound guided approach enhanced the average success regarding the PICC insertion, particularly for the subset with a poor condition in the elbow super?cial vein. Due to the items that emerged in the PICC process, the effective prevention prior to surgery and treatment during the operation would be necessary. 展开更多
关键词 B-ULTRASOUND PICC Seldinger approach problems analysis NURSE
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Finite element analysis of elasto-plastic plate bending problems using transition rectangular plate elements 被引量:4
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作者 B. Kanber O. Yavuz Bozkurt 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第4期355-365,共11页
In this work, the finite element analysis of the elasto-plastic plate bending problems is carried out using transition rectangular plate elements. The shape functions of the transition plate elements are derived based... In this work, the finite element analysis of the elasto-plastic plate bending problems is carried out using transition rectangular plate elements. The shape functions of the transition plate elements are derived based on a practical rule. The transition plate elements are all quadrilateral and can be used to obtain efficient finite element models using minimum number of elements. The mesh convergence rates of the models including the transition elements are compared with the regular element models. To verify the developed elements, simple tests are demonstrated and various elasto-plastic problems are solved. Their results are compared with ANSYS results. 展开更多
关键词 Finite element method Transition plate elements Elasto-plastic analysis. Plate bending problems
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