数值函数
- 与 数值函数 相关的网络例句 [注:此内容来源于网络,仅供参考]
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By applying contour integral method and high-order displacement functionsof MM,we obtain the accurate stress intensity factors of mixed-mode crack.Then,the open crack propagation of the mixed mode I and II is simulated by means oftheories of linear elastic fracture mechanics.This provides a simple and effectivenumerical way for crack evolvement studying.
接着,文中采用围线积分法和流形方法的高阶位移函数来计算得到比较准确的混合型裂纹尖端的应力强度因子,然后基于线弹性断裂力学的裂纹扩展准则,用流形方法实现了平面I-II混合型张裂纹扩展的数值模拟,为数值方法研究裂纹的演化行为提供了一条简单而有效的途径。
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The convergence theorem of the neural networks algorithm and the theorem of numerical integration solution and its inferences are presented and proved.
摘要该文提出了一种基于三角基函数神经网络算法求解数值积分的新方法,提出并证明了神经网络算法的收敛定理和数值积分的求解定理及推论。
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This algorithm is proposed on the basis of the thought as follovvs: as for three dimensional Euclid space, the feasible region of any linear programming problem is a extended convex polyhedron, of which surface is consisted of some planes, and its objective function can be regarded as a parallel plane pencil with objective function value acting as parameter.
如果线性规划问题有最优解,那么过可行域的一已知顶点必至少存在这样一条棱——它以该己知顶点为一端点,可行域的另一顶点为另一端点,并使目标函数在另一端点的函数值优于己知端点的函数值,否则,该己知点就是线性规划问题的最优解。
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This study uses the height function to track the free surface, and the body-fitted coordinate system is used to generate a coordinate surface coindent with the boundary contours in the physical plate.
为求解本研究的流动现象,除了以高度函数法追踪液面外,并以物体嵌合座标系统克服翼形的不规则形状,同时采用SIMPLE数值法来处理整个数值运算过程,并配合交替方向隐式A.D.I。
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Numerical examples are studied to demonstrate the accuracy of the proposed method and to investigate the distribution of the optimal stiffness of the elastic restraints, the deformation of the elastic restraints and deflection of the stiffened plate for stiffened plate with different number of stiffeners, different cross section of stiffeners and different thickness of plate.
本研究利用牛顿法提出一个数值程序以求得使目标函数有最小值且满足拘束条件的弹性支承刚度,即求得最佳化的弹性支承刚度。本研究以数值例题探讨不同加劲板之最佳化的弹性支承刚度,弹性支承变形的分布及加劲板的最大挠度。
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The influences of the shock thickness and Alfven waves on the particle acceleration by diffusive shock waves are numerically studied through solving one-dimensional diffusive equation including the second-order Fermi effect. It is shown that the spectral index of the energetic particles strongly depends on the shock thickness. For example, the spectral index increases from 2.1 to 3.7 in the low energy range of 3-10 MeV and from 2.5 to 5.0 in the high energy range of 20-60 MeV as the thickness increases. The spectral index decreases from 4.3 to 3.1 as the particle injection energy increases. The spectral index decreases from 4.0 to 1.8 at the quasi-steady stage with the enhancement of the compression ratio from 2 to 4. The results indicate that under the influence of Alfven waves, the energetic particle spectrum at lower energy becomes flat and the spectral index decreases from 2.5 to 0.6 in the low energy range of 3-10 MeV and from 11.6 to 5.0 in the high energy range of 20-60 MeV. At the same time, the rollover energy reaches 19.6 MeV. The spectral index decreases from 5.8 to 2.9 as the energy density of Alfven waves increase. All these results are basically consistent with the theoretical models, as well as the observations of typical energetic particle events.
通过数值求解包含二阶费米加速的一维扩散方程,探讨在准平行激波条件下激波厚度和级联阿尔芬波对粒子加速的影响,研究粒子分布函数的演化与激波厚度和阿尔芬波强度的内禀关系,计算结果表明:(1)考虑激波厚度时,谱指数明显依赖于激波厚度,随着厚度从0.32增大到2.56,低能端(3-10MeV)谱指数逐渐从2.1增加到3.7,高能端(20-60MeV)谱指数从2.4增大到5.0,能谱逐渐变软;当初始注入粒子动量增大1.3倍,质子能谱指数从4.3减小到3.1,且与零厚度激波加速的谱指数差值缩小;厚度不变时,随着压缩比从2增加到4,准稳态分布时低能端(3-10MeV)粒子能谱指数逐渐从4.0减小到1.8谱变硬;(2)在级联阿尔芬波的影响下,随着时间的增大,粒子在低能处(3-10MeV)的谱指数从2.5减小到0.6高能端(20-60MeV)谱指数从11.6减小到5.0,能谱变硬,拐点能量值从7.5MeV增大到为19.6MeV;随着波的能量密度增大,谱指数从5.8减小到2.9,这表明阿尔芬波强度越大,加速效率越高,通过与激波厚度解析结果和高能粒子事件的观测能谱比较发现两者是一致的,说明数值模拟结果是可靠的。
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In this paper,taking advantage of some properties of Gamma function,we get the explicit solution. Some simulation results are also given in this paper. In chapter three, we discuss the problem under censored data in three circumstances.
一直以来,对Weibull分布参数的矩估计都是采用数值方法求解,本文利用Gamma函数的一些性质,得到了估计的显式解,并从理论和数值模拟说明此种方法相比其它方法的优越性。
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Under the one-dimensional situation, it introduces mainly the Newton-Cotes formula, the Gaussian quadrature formula, the numerical integration rule of sharp oscillatory function, the numerical integration rule by the methods of sampling and so on.
在一维情形下,主要介绍了Newton-Cotes公式,Gauss型求积法则,急速振荡函数的数值积分法则,抽样法求数值积分的法则等。
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In order to reasonably depict four basic problems with friction, one Coulomb friction new form in first Kirchhoff stress is proposed to deal with finite deformation problems, other Coulomb friction form in incremental mode to elastoplastic flow theory; Hilbert function spaces concerning elastoplastical problems with friction are established, so it makes all operations and calculations in the treatise standardized within the scope of reasonably topologic structure; In view of functional extremum, the equivalence between generalized variational inequalities principles in elastoplasticity with friction and corresponding basic problems are testified by inducing Lagrangian multipliers, so it provides a rationally theoretical basis for numerical methods in elastoplasticity with friction; From the viewpoint of variational inequality, the theory of generalized variational inequalities in elasticity and elastoplasticity with frictional constraint is studied, and the uniqueness and existence of the solution of FEM is proofed under the proposed conditions of stress compatibility, and them FEM approximation and a discrete solution are discussed; Based on the principles of generalized variational inequalities in elastoplasticity with friction, direct generalized variational inequalities methods is pretended, which is a natural generalization and development of direct variational methods; Using generalized variational inequalities methods, some examples in metal forming including plane deformation, upset and extrusion are analyzed and the results prove that all the theories and methods in the paper are right, feasible, accurate and advanced.
主要内容有:为了合理地描述金属塑性成形中摩擦约束弹性、弹塑性基本问题,提出和研究了有限变形下以Kirchhoff第一应力表示的Coulomb摩擦定律形式和弹塑性流动理论下以增量形式表示的Coulomb摩擦定律表示形式;系统建立了摩擦约束弹塑性问题的Hilbert函数空间,使本文规范在一个具有合理的代数拓扑结构内进行一切操作和运算;利用Lagrange乘子,从泛函极值的角度系统地阐述和论证了一系列摩擦约束弹性、弹塑性广义变分不等原理与相应的实际问题之间的等价性,它为处理摩擦约束的弹塑性力学数值方法提供了合理的理论基础;从变分不等式的角度出发,阐述了对应于摩擦约束弹性、弹塑性问题的广义变分不等式理论,首次提出了在应力相容性条件下,它的有限元解具有存在唯一性,进而讨论了其有限元近似及离散解法;基于摩擦约束弹塑性广义变分不等式原理,首次提出了直接广义变分不等式方法,这一方法是直接变分法的合理推广和发展;利用直接广义变分不等式方法对金属压力加工中的平面变形问题、镦粗、挤压等塑性成形问题进行了分析计算,验证了该理论和数值算法的正确性、实用性、精确性和优越性。
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Numerical test shows that the method presented in this paper can be applied in the lateral inhomogeneity study of the Earth Interior.
数值检验表明,本文所提出的横向非均匀介质接收函数的数值模拟与偏移成像可用于地球内部介质横向不均匀性的研究。
- 推荐网络例句
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The split between the two groups can hardly be papered over.
这两个团体间的分歧难以掩饰。
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This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.
这种做法不仅鼓励了更多的反应,而且减少跟风的可能性。
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The new PS20 solar power tower collected sunlight through mirrors known as "heliostats" to produce steam that is converted into electricity by a turbine in Sanlucar la Mayor, Spain, Wednesday.
聚光:照片上是建在西班牙桑路卡拉马尤城的一座新型PS20塔式太阳能电站。被称为&日光反射装置&的镜子将太阳光反射到主塔,然后用聚集的热量产生蒸汽进而通过涡轮机转化为电力