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Extreme mechanics 预览
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作者 Xiaojing Zheng 《力学快报:英文版》 CAS CSCD 2020年第1期1-7,共7页
With the development of cutting-edge sciences and new technologies,we have to consider the size,the density,the hardness,the stiffness and other properties of engineering materials and structures beyond the convention... With the development of cutting-edge sciences and new technologies,we have to consider the size,the density,the hardness,the stiffness and other properties of engineering materials and structures beyond the conventional ranges,as well as their mechanical behavior in extreme environments,such as ultra-conventional temperature,speed,physical and chemical fields,and severe weather,and more effective theories and methods of mechanics are required.This paper first gives the fundamental definition and the scientific connotation of extreme mechanics,then reviews the studies of extreme mechanics from three aspects:the extreme properties,the extreme loads,and the discipline development,as well as major engineering and scientific challenges.The characteristics of extreme mechanics and major challenges in the aspects of mechanical theory,computational methods and experimental techniques are discussed.Prospectivei developments of extreme mechanics are suggested. 展开更多
关键词 Extreme mechanics Extreme properties Extreme loads Discipline development
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神经动力学与力学 预览
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作者 陆启韶 《动力学与控制学报》 2020年第1期6-10,共5页
本文回顾力学研究体系的发展,简要介绍神经动力学的主要内容及其作用,探讨神经动力学与力学的密切关系,并提出一些研究展望。
关键词 力学 脑科学 神经动力学 神经调控 神经疾病 类脑智能
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体育人类工效学研究的问题向度与学理思考 预览
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作者 王聃 何胜保 《体育与科学》 CSSCI 北大核心 2020年第1期43-47,111共6页
体育人类工效学是通过建立人、机械、环境之间的交互关系,以提高体育教学、运动训练、大众健身服务工作绩效的科学体系。探索体育人类工效学研究的基本问题旨在用"人学"的思维方式来解释体育之道德、精神、生命哲学的实质范畴... 体育人类工效学是通过建立人、机械、环境之间的交互关系,以提高体育教学、运动训练、大众健身服务工作绩效的科学体系。探索体育人类工效学研究的基本问题旨在用"人学"的思维方式来解释体育之道德、精神、生命哲学的实质范畴,并借用机械学原理改进体育器械工具技术,开发"实用性"和"器用性"运动装备,为现代体育形态演进效度提供科技支持,以及发挥体育运动场域自然环境、社会环境和技术环境空间结构上的补偿效应,维护体育科学发展环境系统的生态平衡。通过对体育人类工效学学理框架的梳理,认为人、物的双重作用,及二者之间的辩证互动发展演化构成了体育科学认知方式的逻辑起点;建立"人"与"环境"的和谐辩证匹配关系,为人类体育活动创设绿色健康的运动空间;解决"人"与"物"、"人"与"环境"单向度配置关系,发挥"物"与"环境"的辅助功能,有助于形成三维立体协同治理的文化生态结构范式。 展开更多
关键词 体育人类工效学 人学 机械学 环境学 “人、物、环境”协同
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“武器毁伤中的力学”新生研讨课教学实践 预览
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作者 卢芳云 张舵 《高等教育研究学报》 2020年第1期110-115,共6页
针对军校大一新生特点和国防科技大学的办学定位,我校从2012年开始规划并开设了“武器毁伤中的力学”等一系列新生研讨课。本文探讨了“武器毁伤中的力学”这门新生研讨课的教学模式,认为可以通过现实诱发兴趣,通过学术深化思考,使学员... 针对军校大一新生特点和国防科技大学的办学定位,我校从2012年开始规划并开设了“武器毁伤中的力学”等一系列新生研讨课。本文探讨了“武器毁伤中的力学”这门新生研讨课的教学模式,认为可以通过现实诱发兴趣,通过学术深化思考,使学员同时收获知识和理念,顺利实现从高中生到大学生的观念转变,并在作者开设的新生研讨课“武器毁伤中的力学”上进行了此教学模式的实践。 展开更多
关键词 新生研讨课 教学模式 力学 毁伤效应
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A new non-perturbative approach in quantum mechanics for time-independent Schr?dinger equations
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作者 ShiJun Liao 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2020年第3期70-81,共12页
A new non-perturbative approach is proposed to solve time-independent Schr?dinger equations in quantum mechanics.It is based on the homotopy analysis method(HAM)that was developed by the author in 1992 for highly nonl... A new non-perturbative approach is proposed to solve time-independent Schr?dinger equations in quantum mechanics.It is based on the homotopy analysis method(HAM)that was developed by the author in 1992 for highly nonlinear equations and has been widely applied in many fields.Unlike perturbative methods,this HAM-based approach has nothing to do with small/large physical parameters.Besides,convergent series solution can be obtained even if the disturbance is far from the known status.A nonlinear harmonic oscillator is used as an example to illustrate the validity of this approach for disturbances that might be one thousand times larger than the possible superior limit of the perturbative approach.This HAM-based approach could provide us rigorous theoretical results in quantum mechanics,which can be directly compared with experimental data.Obviously,this is of great benefit not only for improving the accuracy of experimental measurements but also for validating physical theories. 展开更多
关键词 non-perturbative series homotopy analysis method quantum mechanics
个体化导板辅助全膝关节置换运动学对线技术 预览
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作者 温亮 王志为 《中华关节外科杂志(电子版)》 CAS CSCD 2020年第1期85-91,共7页
大部分自然人群膝关节存在不同程度的生理内翻或外翻,而目前广泛应用的全膝关节置换机械学对线技术并没有充分尊重这种生理变异,而把下肢中立位对线作为对线目标。有学者认为这可能与膝关节置换较低的术后满意率相关。在此背景下出现了... 大部分自然人群膝关节存在不同程度的生理内翻或外翻,而目前广泛应用的全膝关节置换机械学对线技术并没有充分尊重这种生理变异,而把下肢中立位对线作为对线目标。有学者认为这可能与膝关节置换较低的术后满意率相关。在此背景下出现了一种更为尊重自然膝关节解剖形态的对线方式——运动学对线,由于该方法可能有助于减少术中软组织松解,改善膝关节术后功能并提高病人的满意率,所以近年来受到广泛关注。作者医院是国内最早使用个体化截骨导板进行运动学对线膝关节置换的单位之一。本文总结了该技术的术前规划、手术技巧和陷阱、相关理论以及临床和实验室证据等方面内容,以帮助读者全面理解运动学对线技术。 展开更多
关键词 关节成形术 置换 力学
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浅谈力学及CAE技术在机械设计专业及机械学科发展中的意义 预览
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作者 杨莎莎 沈承 《教育教学论坛》 2020年第4期171-172,共2页
文章从培养学生、学科发展的角度,探讨了力学及CAE技术在机械设计专业及机械学科发展中的重要意义。
关键词 力学 CAE 机械设计
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Development of a multiple level underground limestone mine from geology through mine planning 预览
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作者 Christopher Newman David Newman Robert Dupuy 《矿业科学技术学报:英文版》 CSCD 2020年第1期63-67,共5页
The development of a multiple level underground mine is a complex task in which geology,engineering,ground control,and unit operations are integrated into a single mine design.The components are interdependent and mus... The development of a multiple level underground mine is a complex task in which geology,engineering,ground control,and unit operations are integrated into a single mine design.The components are interdependent and must function cohesively to ensure a profitable underground mining operation.To optimize reserve recovery,mine planning should begin from the lowest level and progress up.This limits any misjudgments or oversights of a given level affecting the underlying levels and ensures the ability to maximize recovery from each level.Mine planning should start with the exploration and characterization of the geologic setting.Once the reserve geology and quality is well understood,then mine planning can begin with respect to the following:(1)orientation of mine works with respect to horizontal stress;(2)access to the reserve;(3)determination of opening widths;(4)selection of back,floor horizons and pillar centers;(5)selection of development and secondary mining heights;(6)appropriate inter-burden thicknesses;and(7)examining the stability of the multiple level mine through numerical modeling.The multiple level mine design process and decisions are presented through a case history example.The theme is that there is one opportunity to"get it right"and many chances to overlook a small aspect within the design that will plague the mine throughout all levels and through the entirety of its operating life. 展开更多
关键词 LIMESTONE Mine planning GEOLOGY Multiple level Rock mechanics
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地方行业特色工科院校力学学科发展困境及几点建议和呼吁 预览
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作者 罗威 黄宜胜 +1 位作者 田东方 叶永 《教育教学论坛》 2020年第4期113-115,共3页
以湖北某省属高校工程力学学科为例,讨论和分析了目前在地方行业特色工科院校中力学学科发展存在的困难,并详细研究了造成这些困难的原因,提出了地方行业特色院校力学学科突破发展困境的几点建议和呼吁。
关键词 力学学科 发展困难 行业特色
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物理学专业《力学》课程教学改革的探索 预览
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作者 李钊 《教育教学论坛》 2020年第10期154-155,共2页
《力学》是物理学专业学生必修的基础课程,与《光学》《热学》《电磁学》和《原子物理学》合成"五小力学"。目前的课程教学中存在诸多问题,文章从教学方法、教学内容和考核方法等方面着手,提出了一些改革建议。
关键词 物理学专业 《力学》 教学改革
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Designer substrates and devices for mechanobiology study 预览
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作者 Wang Xi Delphine Delacour Benoit Ladoux 《半导体学报:英文版》 EI CAS CSCD 2020年第4期81-88,共8页
Both biological and engineering approaches have contributed significantly to the recent advance in the field of mechanobiology.Collaborating with biologists,bio-engineers and materials scientists have employed the tec... Both biological and engineering approaches have contributed significantly to the recent advance in the field of mechanobiology.Collaborating with biologists,bio-engineers and materials scientists have employed the techniques stemming from the conventional semiconductor industry to rebuild cellular milieus that mimic critical aspects of in vivo conditions and elicit cell/tissue responses in vitro.Such reductionist approaches have help to unveil important mechanosensing mechanism in both cellular and tissue level,including stem cell differentiation and proliferation,tissue expansion,wound healing,and cancer metastasis.In this mini-review,we discuss various microfabrication methods that have been applied to generate specific properties and functions of designer substrates/devices,which disclose cell-microenvironment interactions and the underlying biological mechanisms.In brief,we emphasize on the studies of cell/tissue mechanical responses to substrate adhesiveness,stiffness,topography,and shear flow.Moreover,we comment on the new concepts of measurement and paradigms for investigations of biological mechanotransductions that are yet to emerge due to on-going interdisciplinary efforts in the fields of mechanobiology and microengineering. 展开更多
关键词 designer substrates and devices MICROFABRICATION MECHANOBIOLOGY microengineering tissue mechanics MICROFLUIDICS
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体育运动中的滞空及其形成机制研究 预览
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作者 赵西堂 李晓琨 《广州体育学院学报》 北大核心 2020年第2期73-76,共4页
滞空是篮球、排球、跳远、武术等体育运动项目中常常提到的概念,也是体育运动中确实存在的一种现象,即运动员跳起后人体的头部和上体在空中停留的现象;这一现象曾因看似违背经典力学定律而备受质疑。研究通过梳理相关文献资料并结合运... 滞空是篮球、排球、跳远、武术等体育运动项目中常常提到的概念,也是体育运动中确实存在的一种现象,即运动员跳起后人体的头部和上体在空中停留的现象;这一现象曾因看似违背经典力学定律而备受质疑。研究通过梳理相关文献资料并结合运动生理学和运动生物力学相关知识,对滞空现象存在的本质进行了全面的分析,结果表明:滞空现象确实存在也并不违背相关运动学定律;滞空现象是运动员通过巧妙改变自身重心的位置来实现的,其形成机制包括以下三个方面:一、充分利用最高点前后人体纵向速度较小的特点;二、通过运动员肢体的相对运动改变了人体重心的相对位置;三、通过腹式逆呼吸的方法改变身体重心相对位置。 展开更多
关键词 滞空 形成机制 动作变化 腹式逆呼吸
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Strength properties and evolution laws of cracked sandstone samples in re-loading tests 预览
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作者 Yijiang Zong Lijun Han +1 位作者 Qinbin Meng Yingchao Wang 《矿业科学技术学报:英文版》 CSCD 2020年第2期251-258,共8页
To study the strength properties and evolution laws of cracked sandstone samples in re-loading tests,strength and damage evolution properties of intact sandstone samples were first analyzed through the triaxial compre... To study the strength properties and evolution laws of cracked sandstone samples in re-loading tests,strength and damage evolution properties of intact sandstone samples were first analyzed through the triaxial compression tests carried on TAW-2000 microcomputer control electro-hydraulic servo rock triaxial test system.Damage evolution models were established based on dilatancy properties realizing the real-time and quantitative evaluation of samples damage state in loading process.On this basis,samples with different damage were obtained by pre-peak,peak point,post-peak and residual strength stage unloading tests in the loading process of intact samples.The characteristics of the stress-strain curves and strength evolution laws were studied through the re-loading tests of samples with different damage under different stress states.The experimental results showed that the slope of stress-strain curves,peak strength and residual strength of cracked samples increased linearly with confining pressure and decreased linearly with damage.The equivalent cohesion decreased with damage in the exponential decay curves.The mechanics properties of samples transformed from strain softening to strain hardening with damage. 展开更多
关键词 Rock mechanics DAMAGE Re-loading Strength characteristics Strain hardening
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A New Celestial Mechanics Dynamics of Accelerated Systems 预览
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作者 Gabriel Barceló 《应用数学与应用物理(英文)》 2019年第8期1732-1754,共23页
We present in this text the research carried out on the dynamic behavior of non-inertial systems, proposing new keys to better understand the mechanics of the universe. Applying the field theory to the dynamic magnitu... We present in this text the research carried out on the dynamic behavior of non-inertial systems, proposing new keys to better understand the mechanics of the universe. Applying the field theory to the dynamic magnitudes circumscribed to a body, our research has achieved a new conception of the coupling of these magnitudes, to better understand the behavior of solid rigid bodies, when subjected to multiple simultaneous, non-coaxial rotations. The results of the research are consistent with Einstein’s theories on rotation;however, we propose a different mechanics and complementary to classical mechanics, specifically for systems accelerated by rotations. These new concepts define the Theory of Dynamic Interactions (TDI), a new dynamic model for non-inertial systems with axial symmetry, which is based on the principles of conservation of measurable quantities: the notion of quantity, total mass and total energy. This theory deduces a general equation of motion for bodies endowed with angular momentum, when they are subjected to successive non-coaxial torques. 展开更多
关键词 MECHANICS DYNAMIC INTERACTIONS Non-Inertial SYSTEMS DYNAMIC Coupling Celestial MECHANICS
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SOME PROBLEMS IN RADIATION TRANSPORT FLUID MECHANICS AND QUANTUM FLUID MECHANICS
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作者 Boling Guo Jun Wu 《应用数学年刊:英文版》 2019年第2期111-125,共15页
We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport flu... We introduce the radiation transport equations, the radiation fluid mechanics equations and the fluid mechanics equations with quantum effects. We obtain the unique global weak solution for the radiation transport fluid mechanics equations under certain initial and boundary values. In addition, we also obtain the periodic region problem of the compressible N-S equation with quantum effect has weak solutions under some conditions. 展开更多
关键词 RADIATION transport equation RADIATION FLUID MECHANICS EQUATIONS FLUID MECHANICS EQUATIONS with QUANTUM effects
A regularization scheme for explicit level-set XFEM topology optimization
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作者 Markus J.GEISS Jorge L.BARRERA +1 位作者 Narasimha BODDETI Kurt MAUTE 《机械工程前沿:英文版》 CSCD 2019年第2期153-170,共18页
Regularization of the level-set(LS)field is a critical part of LS-based topology optimization(TO)approaches.Traditionally this is achieved by advancing the LS field through the solution of a Hamilton-Jacobi equation c... Regularization of the level-set(LS)field is a critical part of LS-based topology optimization(TO)approaches.Traditionally this is achieved by advancing the LS field through the solution of a Hamilton-Jacobi equation combined with a reinitialization scheme.This approach,however,may limit the maximum step size and introduces discontinuities in the design process.Alternatively,energy functionals and intermediate LS value penalizations have been proposed.This paper introduces a novel LS regularization approach based on a signed distance field(SDF)which is applicable to explicit LSbased TO.The SDF is obtained using the heat method(HM)and is reconstructed for every design in the optimization process.The governing equations of the HM,as well as the ones describing the physical response of the system of interest,are discretized by the extended finite element method(XFEM).Numerical examples for pro?blems modeled by linear elasticity,nonlinear hyperelasticity and the incompressible Navier-Stokes equations in two and three dimensions are presented to show the applicability of the proposed scheme to a broad range of design optimization problems. 展开更多
关键词 LEVEL-SET REGULARIZATION EXPLICIT level-sets XFEM CutFEM topology optimization heat method SIGNED distance field nonlinear structural MECHANICS fluid MECHANICS
应用型本科土木工程专业力学课程教学与实践改革研究 被引量:1
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作者 吴从晓 黄青青 +2 位作者 钟星鸣 侯庆华 阴凡 《中国多媒体与网络教学学报(电子版)》 2019年第6期195-196,共2页
对于以应用型人才培养为办学定位的本科院校,其应立足于高层次应用型技术型人才的培养为目标,在教学过程中应体现实践、学生动手等能力的培养。对于土木工程专业的必修的力学课,如何提高学生的理解、实践运用能力,需对课程教学、实践及... 对于以应用型人才培养为办学定位的本科院校,其应立足于高层次应用型技术型人才的培养为目标,在教学过程中应体现实践、学生动手等能力的培养。对于土木工程专业的必修的力学课,如何提高学生的理解、实践运用能力,需对课程教学、实践及考核方式进行改革,为应用型本科院校土木工程专业力学课程教学提供参考。 展开更多
关键词 应用型 力学 教学改革
Fluid Mechanics and Heat-Transfer Operations Combination Involved in Urea Unit of Fertilizer Complex 预览
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作者 Muhammad Imran Rashid Naveed Ramzan 《非金属材料科学(英文)》 2019年第1期5-10,共6页
Fertilizer plants are most complex plants in the world (Rashid et al., 2013, Process Safety Progress) and its good opportunity to learn science from operations involved in these plants. Fluid mechanics and heat transf... Fertilizer plants are most complex plants in the world (Rashid et al., 2013, Process Safety Progress) and its good opportunity to learn science from operations involved in these plants. Fluid mechanics and heat transfer operations combination involved in fertilizer complexes are explored in this article. 展开更多
关键词 FERTILIZER plants FERTILIZER COMPLEX Fluid MECHANICS HEAT-TRANSFER UREA
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Supporting characteristics analysis of constant resistance bolts under coupled static-dynamic loading
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作者 CHEN Feng TANG Chun-an +2 位作者 SUN Xiao-ming MA Tian-hui DU Yan-hong 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1160-1169,共10页
To study the tensile mechanical properties of constant resistance bolts, the RFPA(Rock Failure Process Analysis) statics software is used to perform a uniaxial tensile test on a constant resistance bolt. The numerical... To study the tensile mechanical properties of constant resistance bolts, the RFPA(Rock Failure Process Analysis) statics software is used to perform a uniaxial tensile test on a constant resistance bolt. The numerical test results show that the plastic strain value is 12 times the magnitude of the elastic strain. During plastic deformation, the fluctuation in the stress magnitude is relatively stable, indicating that the bolt has good constant resistance characteristics. The numerical test results are in good agreement with the laboratory test results of M.C. He, and the accuracy and reliability of the numerical test method are verified. Therefore, the RFPA software with coupled static-dynamic loading is further adopted to study the supporting effects of traditional bolts and constant resistance bolts under coupled staticdynamic loading. The numerical comparison of the test results show that the constant resistance bolts can effectively control the deformation amount and rate of the laneway surrounding rock, reduce the total and rate of increase in the accumulated acoustic emissions,decrease the stress on the units in the model and protect the stability of the laneway. This paper verifies that a constant resistance bolt has better impact resistance mechanical properties than those of a traditional bolt and provides an effective way to control rock burst and soft rock that is prone to large deformation damage. 展开更多
关键词 Rock mechanics COUPLED static-dynamic loading Deep laneway CONSTANT RESISTANCE bolt RFPA
基于复变函数的含孔边裂纹结构弹性断裂力学问题研究 预览
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作者 皮建东 《科技通报》 2019年第4期1-4,10共5页
针对当前含孔边裂纹结构弹性断裂力学研究方法存在的研究结果与实际结果吻合性差、研究结果用户满意度低的问题,提出基于复变函数的含孔边裂纹结构弹性断裂力学问题研究方法。基于裂纹受力条件以及受力状况,将含孔边裂纹划分成两类:Ⅰ... 针对当前含孔边裂纹结构弹性断裂力学研究方法存在的研究结果与实际结果吻合性差、研究结果用户满意度低的问题,提出基于复变函数的含孔边裂纹结构弹性断裂力学问题研究方法。基于裂纹受力条件以及受力状况,将含孔边裂纹划分成两类:Ⅰ型裂纹和Ⅱ型裂纹。发现Ⅰ型裂纹的上下表面是相对张开的,Ⅱ型裂纹的上下表面沿横轴相对滑开。根据含孔边裂纹分析情况,利用复变函数法对含孔边裂纹结构弹性断裂力学问题予以解决,通过构建保角映射函数,并将无限放大的含孔边裂纹外部区域映射至单位圆内部或者是上半面,以此解决裂纹结构平面弹性相关问题,得到裂纹应力强度因子,实现含孔边裂纹结构弹性断裂力学研究。实验结果表明,基于复变函数的含孔边裂纹结构弹性断裂力学研究方法分析结果与实际情况吻合度最高为99%,研究结果用户满意度相较当前方法更高。所提方法整体性能优越,可为该领域研究提供一定的借鉴。 展开更多
关键词 复变函数 含孔边裂纹结构 断裂 力学
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