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Research on Teaching Methods of Flight Control Principles
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作者 Dongying Li 《Journal of Electronic Research and Application》 2024年第3期155-160,共6页
With the rapid development of China’s civil aviation industry,the teaching method of operating knowledge of flight principles has changed greatly,which creates a good implementation environment to improve the safety ... With the rapid development of China’s civil aviation industry,the teaching method of operating knowledge of flight principles has changed greatly,which creates a good implementation environment to improve the safety of civil aviation in our country.At present,the main training content of air route transport pilots in China is basic aviation theory,initial flight training,airline modification,etc.The principles of flight control are an important part of basic aviation theoretical knowledge training,which will involve a large number of flight technology training content,instructors will also be based on the pilot type.Teaching flight control theory and practical knowledge requires relatively high theoretical learning ability of students,and the learning effect of this part of theoretical knowledge will directly affect the quality of subsequent learning,but also directly affect the effectiveness of flight training.This paper focuses on the analysis of the basic concepts of flight control,studies the existing problems in the teaching of flight control principles,summarizes the teaching measures of flight control principles,aiming to provide a reference to teaching personnel. 展开更多
关键词 Flight control principle knowledge Virtual simulation Teaching method
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SEMI-INVERSE METHOD AND GENERALIZED VARIATIONAL PRINCIPLES WITH MULTI-VARIABLES IN ELASTICITY 被引量:2
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作者 何吉欢 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第7期797-808,共12页
Semi-inverse method, which is an integration and an extension of Hu's try-and-error method, Chien's veighted residual method and Liu's systematic method, is proposed to establish generalized variational pr... Semi-inverse method, which is an integration and an extension of Hu's try-and-error method, Chien's veighted residual method and Liu's systematic method, is proposed to establish generalized variational principles with multi-variables without arty variational crisis phenomenon. The method is to construct an energy trial-functional with an unknown function F, which can be readily identified by making the trial-functional stationary and using known constraint equations. As a result generalized variational principles with two kinds of independent variables (such as well-known Hellinger-Reissner variational principle and Hu-Washizu principle) and generalized variational principles with three kinds of independent variables (such as Chien's generalized variational principles) in elasticity have been deduced without using Lagrange multiplier method. By semi-inverse method, the author has also proved that Hu-Washizu principle is actually a variational principle with only two kinds of independent variables, stress-strain relations are still its constraints. 展开更多
关键词 variational principle in elasticy Chien's generalized variational principles Hu-Washizu principle semi-inverse method trial-functional variational crisis
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Base force element method of complementary energy principle for large rotation problems 被引量:8
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作者 Yijiang Peng Yinghua Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第4期507-515,共9页
Using the concept of the base forces, a new finite element method (base force element method, BFEM) based on the complementary energy principle is presented for accurate modeling of structures with large displacemen... Using the concept of the base forces, a new finite element method (base force element method, BFEM) based on the complementary energy principle is presented for accurate modeling of structures with large displacements and large rotations. First, the complementary energy of an element is described by taking the base forces as state variables, and is then separated into deformation and rotation parts for the case of large deformation. Second, the control equations of the BFEM based on the complementary energy principle are derived using the Lagrange multiplier method. Nonlinear procedure of the BFEM is then developed. Finally, several examples are analyzed to illustrate the reliability and accuracy of the BFEM. 展开更多
关键词 Base force element method (BFEM) Complementary energy principle Lagrange multiplier method Geometrically nonlinear Large rotation
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Modified Lagrange Multiplier Method and Generalized Variational Principle in Fluid Mechanics 被引量:1
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作者 何吉欢 《Advances in Manufacturing》 SCIE CAS 1997年第2期117-122,共6页
The Lagrange multiplier method plays an important role in establishing generalized variational principles notonly in tluid mechallics. but also in elasticity. Sometimes, however, one may come across variational crisi... The Lagrange multiplier method plays an important role in establishing generalized variational principles notonly in tluid mechallics. but also in elasticity. Sometimes, however, one may come across variational crisis(somemultipliers vanish identically). failing to achieve his aim. The crisis is caused by the fact that the Inultipliers are treatedas independent variables in the process of variatioll. but after identification they become functions of the originalindependent variables. To overcome it, a Inodified Lagrange multiplier method or semi-inverse method has beenproposed to deduce generalized varistional principles. Some e-camples are given to illustrate its convenience andeffectiveness of the novel method. 展开更多
关键词 Lagrange multiplier method variational crisis variational principle semi-inverse method trialfunctional
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Principles and Methods for Construction of Lowcarbon Landscape Architecture
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作者 李芸 李静 张浪 《Journal of Landscape Research》 2011年第3期4-6,11,共4页
After illustrating history of low-carbon theory and concept of low-carbon economy,the paper had indentified connotation and principles of low-carbon landscape architecture,pointed out that construction of low-carbon l... After illustrating history of low-carbon theory and concept of low-carbon economy,the paper had indentified connotation and principles of low-carbon landscape architecture,pointed out that construction of low-carbon landscape architecture should follow principles of "site respect,natural power,landscape heterogeneity and nature manifestation".Furthermore,it discussed methods for construction of low-carbon landscape architecture,highlighting rainwater reserve utilization,green landscape structure,effluent purification circulation,architectural materials selection and carbon sink increase by plants.Low-carbon urban landscaping concept and technology provided a new way of thinking for landscaping construction and they were also the urgent needs for construction of low-carbon city. 展开更多
关键词 Low-carbon Low-carbon LANDSCAPE ARCHITECTURE principleS and methodS
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THE RANDOM VARIATIONAL PRINCIPLE AND FINITE ELEMENT METHOD
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作者 张汝清 高行山 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第5期401-406,共6页
In this paper, we introduced the random materials, geometrical shapes, force and displacement boundary condition directly into the functional variational formulations and developed a unified random variational princip... In this paper, we introduced the random materials, geometrical shapes, force and displacement boundary condition directly into the functional variational formulations and developed a unified random variational principle and finite element method with the small parameter perturbation method. Numerical examples showed that the methods have the advantages of the simple and convenient program implementation, and are effective for the random mechanics problems. 展开更多
关键词 variational principle flnite element method perturbation method
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A natural neighbour method based on Fraeijs de Veubeke variational principle for materially non-linear problems
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作者 Xiang Li Serge Cescotto Barbara Rossi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第1期83-93,共11页
The natural neighbour method can be considered as one of many variants of the meshless methods. In the present paper, a new approach based on the Fraeijs de Veubeke (FdV) functional, which is initially developed for... The natural neighbour method can be considered as one of many variants of the meshless methods. In the present paper, a new approach based on the Fraeijs de Veubeke (FdV) functional, which is initially developed for linear elasticity, is extended to the case of geometrically linear but materially non-linear solids. The new approach provides an original treatment to two classical problems: the numerical evaluation of the integrals over the domain A and the enforcement of boundary conditions of the type ui = hi on Su. In the absence of body forces (Fi = 0), it will be shown that the calculation of integrals of the type fA .dA can be avoided and that boundary conditions of the type ui = hi on Su can be imposed in the average sense in general and exactly if hi is linear between two contour nodes, which is obviously the case for tTi = O. 展开更多
关键词 Natural neighbour method Meshless methodFraeijs de Veubeke variational principle DISCRETIZATION Voronoi cell
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Reflection on ELT Methods and Principles from the Perspective of “Post-Method” Framework
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作者 骆园 《海外英语》 2019年第14期270-272,共3页
Over the past decades,the research in ELT methods has already experienced an ongoing transition from method-based pedagogy to post-method pedagogy.With regard to various method-based pedagogy,which is the best and app... Over the past decades,the research in ELT methods has already experienced an ongoing transition from method-based pedagogy to post-method pedagogy.With regard to various method-based pedagogy,which is the best and appropriate method for TEFL in China has been still a controversial and vital issue.By the reflection and critical analysis of my own experience as an EFL learner and of teaching methods and principles in ELT class as a college teacher,this paper mainly demonstrates there is no one so called‘best’or‘right’teaching methods for all from the perspective of Post-method framework which reflects a theoretical construct for teachers to effectively develop a systematic,and coherent pedagogy in their teaching context,aims to provide more instructive reference for ELT and English teachers’development in China. 展开更多
关键词 ELT methodS teaching principleS POST-method PEDAGOGY REFLECTION
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The Principle&Method of Trademark Translation 被引量:1
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作者 孙琳琳 《海外英语》 2010年第4X期95-97,共3页
As a particular form of translation,brand name translation is not simply a matter of finding equivalent expressions in the target language for the source brand name,but a process of transplanting cultures as well,whic... As a particular form of translation,brand name translation is not simply a matter of finding equivalent expressions in the target language for the source brand name,but a process of transplanting cultures as well,which is not easy.In this article,the author expounds the Principle& Method of Trademark Translation in detail. 展开更多
关键词 TRADEMARK TRANSLATION principle method
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Correlation method estimation of the modulation signal in the weak equivalence principle test 被引量:1
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作者 Jie Luo Liang-Cheng Shen +2 位作者 Cheng-Gang Shao Qi Liu Hui-Jie Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期136-142,共7页
In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the fre... In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the free oscillation signal and employ the correlation method to estimate the amplitude of the modulation signal. The data analysis of an experiment shows that the uncertainties of amplitude components of the modulation signal obtained by the correlation method are in agreement with those due to white noise. The power spectral density of the modulation signal obtained by the correlation method is about one order higher than the thermal noise limit. It indicates that the correlation method is an effective way to estimate the amplitude of the modulation signal and it is instructive to conduct a high-accuracy WEP test. 展开更多
关键词 weak equivalence principle test correlation method amplitude estimation thermal noise limit
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Consistency and Validity of the Mathematical Models and the Solution Methods for BVPs and IVPs Based on Energy Methods and Principle of Virtual Work for Homogeneous Isotropic and Non-Homogeneous Non-Isotropic Solid Continua 被引量:1
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作者 Karan S. Surana Emilio N. Alverio 《Applied Mathematics》 2020年第7期546-578,共33页
Energy methods and the principle of virtual work are commonly used for obtaining solutions of boundary value problems (BVPs) and initial value problems (IVPs) associated with homogeneous, isotropic and non-homogeneous... Energy methods and the principle of virtual work are commonly used for obtaining solutions of boundary value problems (BVPs) and initial value problems (IVPs) associated with homogeneous, isotropic and non-homogeneous, non-isotropic matter without using (or in the absence of) the mathematical models of the BVPs and the IVPs. These methods are also used for deriving mathematical models for BVPs and IVPs associated with isotropic, homogeneous as well as non-homogeneous, non-isotropic continuous matter. In energy methods when applied to IVPs, one constructs energy functional (<i>I</i>) consisting of kinetic energy, strain energy and the potential energy of loads. The first variation of this energy functional (<em>δI</em>) set to zero is a necessary condition for an extremum of <i>I</i>. In this approach one could use <i>δI</i> = 0 directly in constructing computational processes such as the finite element method or could derive Euler’s equations (differential or partial differential equations) from <i>δI</i> = 0, which is also satisfied by a solution obtained from <i>δI</i> = 0. The Euler’s equations obtained from <i>δI</i> = 0 indeed are the mathematical model associated with the energy functional <i>I</i>. In case of BVPs we follow the same approach except in this case, the energy functional <i>I</i> consists of strain energy and the potential energy of loads. In using the principle of virtual work for BVPs and the IVPs, we can also accomplish the same as described above using energy methods. In this paper we investigate consistency and validity of the mathematical models for isotropic, homogeneous and non-isotropic, non-homogeneous continuous matter for BVPs that are derived using energy functional consisting of strain energy and the potential energy of loads. Similar investigation is also presented for IVPs using energy functional consisting of kinetic energy, strain energy and the potential energy of loads. The computational approaches for BVPs and the IVPs designed using energy functional and principle of virtual work, their consistency and validity are also investigated. Classical continuum mechanics (CCM) principles <i>i.e.</i> conservation and balance laws of CCM with consistent constitutive theories and the elements of calculus of variations are employed in the investigations presented in this paper. 展开更多
关键词 Energy methods principle of Virtual Work Calculus of Variations Euler’s Equation Mathematical Model Classical and Non-Classical Continuum Mechanics
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Principles of the roof cut short-arm beam mining method (110 method) and its mining-induced stress distribution 被引量:12
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作者 Tao Zhigang Song Zhigang +2 位作者 He Manchao Meng Zhigang Pang Shihui 《International Journal of Mining Science and Technology》 EI CSCD 2018年第3期391-396,共6页
Since the 1960 s, mining science and technology in China has experienced two technical innovations, i.e.the ‘‘Masonry Beam Theory(MBT)" and ‘‘Transfer Rock Beam Theory(TRBT)". Based on those theories, th... Since the 1960 s, mining science and technology in China has experienced two technical innovations, i.e.the ‘‘Masonry Beam Theory(MBT)" and ‘‘Transfer Rock Beam Theory(TRBT)". Based on those theories, the conventional mining method(being called the 121 mining method) was established, consisting of excavating two tunnels with a pillar left for mining a working panel. However, with increasing mining depth,engineering geological disasters in the underground caverns have been frequently encountered. In addition, the use of the coal-pillar mining results in a large amount of coal resources unexploited. In order to address the problems above, the ‘‘Roof Cut Short-Arm Beam Theory(RCSBT), being called the 110 mining method)" was proposed by He Manchao in 2008. The 110 mining method features the mining of one coal seam panel, excavating necessarily only one roadway tunnel and leaving no pillars. Realization of the 110 mining method includes the following steps:(1) directional pre-splitting roof cutting,(2) supporting the roof by using high Constant Resistance Large Deformation bolt/cable(CRLD), and(3) blocking gangue by hydraulic props. This paper presents an overview of the principles, techniques and application of the 110 mining method. Special emphasis is placed on the numerical simulation of the geostress distribution found in the mining panel using the 110 method compared to that of the 121 method. In addition, the stress distribution on the ‘‘short beam" left by the roof cutting when performing the 110 method was also investigated using both numerical simulation and theoretical formulation. 展开更多
关键词 Mining innovation 121 mining method Cutting cantilever beam theory Non-pillar mining 110 mining method
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Study on Accounting Principle and Method of Activity-Based Costing of CIMS Enterprises in China 被引量:1
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作者 丁日佳 杜爱静 +1 位作者 强桂英 王立杰 《International Journal of Mining Science and Technology》 SCIE EI 2000年第2期26-29,共4页
关键词 of CIMS Enterprises in China and method of Activity-Based Costing Study on Accounting principle CIMS ACTIVITY
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A Review of"Some Basic Principles of Teacher Training"and"British and American Methodology"in NEW ORIENTTIONS IN THE TEACHING OF ENGLISH By Peter Strevens 被引量:1
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作者 Che Yongping(Department of Foreign Languages, Kunming Institute of Technology, Kunming 650093) 《昆明理工大学学报(自然科学版)》 CAS 1994年第S1期38-41,共4页
AReviewof"SomeBasicPrinciplesofTeacherTraining"and"BritishandAmericanMethodology"inNEWORIENTTIONSINTHETEACHI... AReviewof"SomeBasicPrinciplesofTeacherTraining"and"BritishandAmericanMethodology"inNEWORIENTTIONSINTHETEACHINGOFENGLISHByPete... 展开更多
关键词 review principles and methodology in TEACHER trainingChinese BOOKS reference materials classification number H319.3
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Principle and mathematical method for inverting stress state of a medium from the remote sensing data
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作者 尹京苑 邓明德 +3 位作者 钱家栋 房宗绯 赵宝宗 刘晓琳 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第4期413-421,共9页
It has been proved through experiments that the electromagnetic radiation energy of a substance will vary when stress acts on the substance. This moment, the electromagnetic radiation energy (observation value) receiv... It has been proved through experiments that the electromagnetic radiation energy of a substance will vary when stress acts on the substance. This moment, the electromagnetic radiation energy (observation value) received by the remote sensor is triggered not only by the substance temperature and also by the stress. Separating quantitatively these two kinds of electromagnetic radiation energy and then inversing the actual temperature state and stress state of a medium is a matter with practical significance in earthquake prediction and stability monitoring for the large-scale geotechnical engineering. In this paper the principle and the mathematical method for inversing stress by using multiband remote sensing data are discussed in detail. A calculation example is listed. 展开更多
关键词 remote sensing data inversing stress principle method
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THE VARIATIONAL PRINCIPLES AND APPLICATION OF NONLINEAR NUMERICAL MANIFOLD METHOD
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作者 骆少明 张湘伟 蔡永昌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第12期1401-1406,共6页
The physical-cover-oriented variational principle of nonlinear numerical manifold method (NNMM) for the analysis of plastical problems is put forward according to the displacement model and the characters of numerical... The physical-cover-oriented variational principle of nonlinear numerical manifold method (NNMM) for the analysis of plastical problems is put forward according to the displacement model and the characters of numerical manifold method (NMM). The theoretical calculating formulations and the controlling equation of NNMM are derived. As an example, the plate with a hole in the center is calculated and the results show that the solution precision and efficiency of NNMM are agreeable. 展开更多
关键词 variational principle numerical manifold method nonlinear analysis plastical flow
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THE VARIATIONAL PRINCIPLE AND APPLICATION OF NUMERICAL MANIFOLD METHOD
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作者 骆少明 张湘伟 蔡永昌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第6期658-663,共6页
The physical-cover-oriented variational principle of numerical manifold method (NMM) for the analysis of linear elastic static problems was put forward according to the displacement model and the characters of numeric... The physical-cover-oriented variational principle of numerical manifold method (NMM) for the analysis of linear elastic static problems was put forward according to the displacement model and the characters of numerical manifold method. ne theoretical calculating formulations and the controlling equation of NMM were derived. As an example, the plate with a hole in the center is calculated and the results show that the solution precision and efficiency of NMM are agreeable. 展开更多
关键词 variational principle numerical manifold method numerical analysis
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Compilation Principles and Methods of China’s First Mongolian Standard in Meteorological Industry
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作者 Ying Chun Yu Gang Han Yanli 《Meteorological and Environmental Research》 CAS 2019年第4期118-121,共4页
Mongolian Terms Commonly Used in Meteorological Services that was issued by the China Meteorological Administration is China s first traditional Mongolian standard in meteorological industry. In the process of formula... Mongolian Terms Commonly Used in Meteorological Services that was issued by the China Meteorological Administration is China s first traditional Mongolian standard in meteorological industry. In the process of formulation, the compilation unit fully complied with the principles of scientificity, practicability, universality and versatility, and used literal translation, free translation, and the combination of literal translation and free translation to translate and compile 71 mongolian terms commonly used in meteorological services. The standard fills the blank of standardization construction of basic traditional Mongolian language in the meteorological industry of China. 展开更多
关键词 METEOROLOGY MONGOLIAN language STANDARD COMPILATION principleS and methodS
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VARIATIONAL PRINCIPLES OF PERFORATED THIN PLATES AND FINITE ELEMENT METHOD FOR BUCKLING AND POST-BUCKLING ANALYSIS
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作者 Yang Xiao Cheng Changjun (Department of Mechanics,Lanzhou University,Lanzhou,730000) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1991年第2期147-156,共10页
On the basis of the general theory of perforated thin plates under large deflections, variational principles with deflection w and stress function F as variables are stated in detail.Based on these princi- ples,finite... On the basis of the general theory of perforated thin plates under large deflections, variational principles with deflection w and stress function F as variables are stated in detail.Based on these princi- ples,finite element method is established for analysing the buckling and post-buckling of perforated thin plates. It is found that the property of element is very complicated,owing to the multiple connexity of the region. 展开更多
关键词 variational principle finite element method perforated thin plate buckling and post-buckling analysis
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THE VIRTUAL WORK PRINCIPLE AND LINEAR COMPLEMEN-TARY METHOD FOR COUPLING ANALYSIS OF ELASTO-PLASTIC DAMAGE STRUCTURE
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作者 马景槐 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第2期185-192,共8页
The virtual displacement principle of elasto-plastic damage mechanics is presented. A linear complementary method for elasto-plastic damage problem is proposed by using FEM technique. This method is applicable to solv... The virtual displacement principle of elasto-plastic damage mechanics is presented. A linear complementary method for elasto-plastic damage problem is proposed by using FEM technique. This method is applicable to solving the damage structure analysis of hardened and softened nonlinear material. 展开更多
关键词 elasto-plastic damage mechanics virtual work principle FEM technique linear complementary method
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