查询词典 approximation theory

The scattering property and target strength of the anchovy in the Yellow Sea are studied numerically based on sound scattering theory and model approximation techniques.

采用声散射理论和目标强度近似模型评估法对黄海鳀鱼的声散射特征和目标强度进行了数值计算与评估研究。

We must seek two main approximation method s of solution, the variation method and perturbation theory

我们必须寻求两个主要的近似解法、变分法和微扰法。

The random phase approximation method and the Feymann-Hellman theorem are used to calculate the seventh order glueball mass of the 2+1-D SU(2) lattice gauge theory.

采用无规相近似方法，用空心图作为试探波函数，利用Feymann Hellman定理计算七阶 2 + 1维SU(2 )格点规范场的胶球质量，在弱耦合区 1/g2 =1。

Contents: A Brief Review of Elementary Quantum Chemistry; An Introduction to Electronic Structure Theory; The Born-Oppenheimer Approximation; Time Evolution of Wavefunctions; Angular Momentum Summary; The Unitary Group Form of the Hamiltonian; Introduction to Hartree-Fock Theory; Permutational Symmetries of Integrals; Notes on Excited Electronic States; The Quantum Harmonic Oscillator; Assigning Symmetries of Vibrational Modes; Notes on Elementary Linear Algebra

内容： 初等量子化学的简评；电子结构理论的介绍；天生奥本海默的接近； Wavefunctions的时间演化；角动量摘要； Hamiltonian的单位的组形式；哈特里-Fock 理论的介绍；积分的Permutational对称性；在令人激动的电子国家上注明；这台量谐波振荡器；分配振动的方式的对称性；在初等线性代数上注明

On the basis of the generalized phase integral approximation and the beam displacement ray mode theory, which are both developed by Chinese acousticians, a fast method for normal modes analyzing including the leaky modes is presented. The application of this method in the coupled mode parabolic equation theory gives an efficient algorithm for both the range dependent problems (CMPE2D) and the three dimensional problems (CMPE3D).

在我国独创的广义相积分理论和波束位移射线简正波理论的基础上，提出了一种可以快速而精确地求解简正波本征值的算法，并将该算法应用于简正波-抛物方程理论，从而实现了二维(CMPE2D)和三维(CMPE3D)声场的快速预报。

Based on the mean spherical approximation integral equation theory, perturbation theory and group contribution concept, a new molecular thermodynamic model was established for the representation of activity coefficient of solvent in the IL-containing systems.

利用平均球近似积分方程理论、微扰理论以及基团贡献的基本思想，本文建立了一个适用于含离子液体体系中溶剂活度系数计算的新的分子热力学模型。

In this case, a decision analysis method based on extension of rough set theory is proposed .This method replaces indiscernibility relation in original rough set theory with the "indiscernibility-similarity-dominance" relation and obtains rough approximation of knowledge, it will not only be able to resolve the aboved-mentioned problems but also deal with inconsistence in decision table.

针对这种情况，给出一种基于扩展粗糙集的决策分析方法，该方法使用&不可区分-相似-优势&关系代替经典粗糙集中的不可区分关系来获取知识的粗糙近似，不但能够解决上述问题而且还能处理决策表中可能存在的不一致现象。

At the early 1980s, is an effective mathematic tool to deal with the uncertain or fuzzy knowledge. Rough rule theory has been widely used in information retrieval, digital library, software engineering and knowledge discovery. Its main idea includes acquisition of rough decision rules by reduction of data under the condition of keeping an invariability of classification capacity. And it basically represents a concept by a pair of approximation sets according to the partition on the given data based on the indiscernibility relation. Rough sets theory is well suited to deal with inconsistency of the rough approximations. So it is a new mathematical tool dealing with vagueness and uncertainty, and has found its applications in many areas such as AI, KDD, pattern recognition and classification and fault diagnosis.

主要完成了以下几个方面的工作：(1)对于高速移动机器人车道线跟踪问题中的规则知识获取，首先阐述了模糊逻辑系统的基本特点、工作原理和基本作法，分析了模糊规则知识获取过于依赖专家经验知识、对于每一个细节几乎都需要人工主观经验的参与、难以处理大数据集样本等方面的不足，进而阐述了粗糙集合理论的基本特点、基于粗糙集合理论的规则获取的关键技术和工作原理，为后续章节中经典粗糙集合模型的扩展及粗糙决策规则集的性能分析做好基础；(2)在经典粗糙集理论及其一般扩展的可变精度粗糙集VPRS的基础上，提出了非均匀可变精度粗糙集模型k-VPRS。

Traditionally, research on the phenomenological theory for neutral kaon system use the effective Htmiltonian theory based on the Wigner-Wesskopf approximation.

1引言 中性K介子系统一直以来是由一个准到弱作用二阶的2X2非厄密有效哈密顿量描述的。

Equidistance point and difference theory in theory of function approximation are studied. Meanwhile, the relation among difference, difference quotient and derivate is revealed. By drawing Lagrange's and Cauchy's theorem of mean on difference and Taylor's formula into difference function, four theorems, such as Lagrange's theorem of mean on difference, are concluded in simple way. On the basis of these conclusions, the asymptotic property of middle point is studied, a series of new conclusions are drawn and the discussions on the asymptotic property of middle point in differential mid-value are summarized.

对函数逼近论中等距节点和差分理论进行了研究，揭示了差分、差商与导数之间的联系；将Lagrange中值定理、Cauchy中值定理、Taylor公式引入到差分函数中，简明地推导出Lagrange差分中值定理等4个定理，并在此基础上对&中间点&的渐近性进行了研究，得出了一系列&中间点&的渐近性的结果，概括了有关文献对微分中值公式的&中间点&的渐近性的讨论；给出的引理改进了函数逼近论的证明方法，精简了函数逼近论中的一些内容。

He knows that he's one of the mostdominant players in the NBA right now.

我知道他现在是联盟里最有统治力的球员之一了。

Using analysis method of BCG , the dissertation analyzed the management of voluntary service organizations .

利用BCG分析方法对我国的志愿服务组织管理进行了分析。