排序方式: 共有62条查询结果,搜索用时 31 毫秒
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本文讨论了计算固体力学发展的基础和背景,并以它在航空航天领域中的应用为例,说明计算力学的应用所带来的益处。还讨论了为进一步发展计算固体力学应深入研究的一些课题。最后简要展望了计算固体力学的发展前景。 相似文献
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Qin Taiyan Nanjing University of Aeronautics Astronautics Nanjing P. R. ChinaYue Jinchao Tang Renji Dept. of Engineering Mechanics Shanghai Jiaotong University Shanghai P. R. China 《Acta Mechanica Solida Sinica》1995,8(1):64-74
By using the analytic theory of hypersingular integral equations in three-dimensional fracture mechanics, the interactions between two parallel planar cracksunder arbitrary loads are investigated. According to the concepts and method of finite-part integrals, a set of hypersingular integral equations is derived, in which theunknown functions are the displacement discontinuities of the crack surfaces. Then itsnumerical method is proposed by combining the finite-part integral method with theboundary element method. Based on the above results, the method for calculating thestress intensity factors with the displacement discontinuities of the crack surfaces ispresented. Finally, several typical examples are calculated and the numerical resultsare satisfactory. 相似文献
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环氧树脂是一类广泛应用的万能胶,其分子中各种官能团的相对热稳定性是实际应用的重要参数。本文用付里叶变换红外光谱为测试手段研究了室温与降解条件(300℃、1小时)下的己固化环氧618树脂,用差谱法得到了固化的环氧618中各官能团的热稳定性次序为:甲基>次甲基>对位取代苯环>醚健>同碳二甲基。 相似文献
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倪勤 《高等学校计算数学学报(英文版)》1998,(1)
A subspace projected conjugate gradient method is proposed for solving large bound constrained quadratic programming. The conjugate gradient method is used to update the variables with indices outside of the active set, while the projected gradient method is used to update the active variables. At every iterative level, the search direction consists of two parts, one of which is a subspace trumcated Newton direction, another is a modified gradient direction. With the projected search the algorithm is suitable to large problems. The convergence of the method is proved and same numerical tests with dimensions ranging from 5000 to 20000 are given. 相似文献
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血清浓度变化对血清荧光光谱的影响 总被引:1,自引:0,他引:1
光谱分析技术应用于血液的某些疾病诊断具有方便、快速的特点.文章采用日本岛津荧光光度计RF5301,研究了血清荧光光谱随血清浓度变化的规律,为通过血液分析进行疾病诊断提供了实验依据.实验结果表明:在不同波长的激发光激励下产生的荧光光谱不同,当用220,230,310~420 nm波长的光激发时,血清的荧光强度随着血清浓度的增加越来越大;而采用240~300 nm波长的光激发时,血清的荧光强度随着血清浓度的增加变得越来越小.实验还发现:当采用220,230,310~420 nrn波长的光激发时,血清的浓度猝灭和吸收作用不明显,主要是激发出的荧光起作用;采用240~300 nm波长的光激发时,血清浓度猝灭和吸收作用明显,导致荧光强度随着血清浓度的增加变得越来越弱.这对研究血清荧光光谱时血清浓度的选择具有参考价值. 相似文献
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王正盛 《高等学校计算数学学报(英文版)》2001,10(2)
1 IntroductionThe solution of large N× N nonsingular unsymmetric( non-Hermitian) sparse sys-tems of linear equationsAx =b, ( 1 )is one of the most frequently encountered tasks in numerical computations.For example,such systems arise from finite difference or finite element approximations to partial differ-ential equationsA major class of methods for solving ( 1 ) is Krylov subspace or conjugate gradienttype methods.Most successful scheme of these methods are based on the orthogonal pro-jec… 相似文献
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FRP疲劳累积损伤理论研究进展 总被引:15,自引:0,他引:15
纤维增强树指复合材料(FRP)已成为高性能结构的先进材料。本文对FRP疲劳累积损伤理论作了详细的回顾,它们可分为剩余寿命模型、剩余刚度模型、耗散能模型、Markov链模型和其它经验公式。还用两个大样本实验数据对这些模型作了分析对比,结果表明:除Yao和Himmel的剩余强度模型略优一些,其它模型则与传统的Miner模型不相上下。 相似文献