查询词典 exponential integral

At the beginning, the thesis offered an analysis on the backgrounds of Unit Integral English Teaching Approach, the reasons for choosing the research topic and its theoretical and practical significance. Through literature review and summary, the origin of Unit Integral English Teaching Approach, its basic conception and present achievements home and abroad were discussed. Then the theoretical support of Unit Integral English Teaching Approach, System Theory, was introduced and its basic axioms and principles were summarized. Upon this base, the experimental framework was put forward and the exemplification of the study was described in details.

本文首先对整体教学法产生的背景、课题选题的缘由、实验的理论和实践意义进行了论述，然后通过文献回顾与综述，阐明了单元整体教学法的起源、基本的概念以及目前国内外相关研究所取得的成果，并对整体教学法的主要理论依据—系统论的基本原理和原则进行了归纳分析，在此基础上提出单元整体教学研究的实验计划，详细描述了实验的实证性研究过程。

There are two difficult points in convolution integral: how to determine the limit of the integral, arid the integrands on the convolution integral.

确定卷积积分的积分限和在相应区间上的被积函数是计算卷积积分的两个难点。

An integral constant expression can involve only literals (2.13), enumerators, const variables or static data members of integral or enumeration types initialized with constant expressions (8.5), non-type template parameters of integral or enumeration types, and sizeof expressions.

整型常量表达式只能带有字面值(2.13)，枚举值，常变量，或是以常量表达式初始化(8.5)的整型或枚举类型的静态数据成员，整型或枚举类型的非类型模板参数，以及 sizeof 表达式。

By utilizing an exponential transformation and piecewise linearization technique,transforming the exponential terms into the sum of absolute terms,and linearizing each absolute term,the original problem can be transformed into a linear programming problem which can be easily solved.

使用指数变换及利用分段线性化技术转变每个指数项为一些带绝对值项的和，再将绝对值项线性化，最终将原问题转化为一个线性规划问题。

Experiments of flow conductivity closure stress of typical propping agent are done, propping agent short-term flow conductivity alteration index is defined, by this, the relation between fissure short-term flow conductivity and closure stress, it is close to exponential relation. 4. Establishing the mathematical simulator of hydraulic fractured well's production in a steady state, finding the relation curve between dimensionless flow conductivity and fracture penetration coefficient by means of calculation and analyses, it is the basis of hydraulic fracture. 5. Expatiating the importance of optimized hydraulic fracturing design in reservoir engineering, advancing the optimizing design method, fracture dimension can be calculated easily when the physical parameters are known. 6. Production rate decline standard curve of vertical fractured wells is achieved by mathematical simulation, when the flow pressure is certain , by asymptotic analyze, this decline curve is close to exponential relation.

完成了国内外典型支撑剂的导流能力闭合应力影响实验，在数据分析中定义了支撑剂短期导流能力变异系数，并由此发现裂缝短期导流能力随闭合应力变化的近似符合指数关系式； 4 建立了一种水力压裂井稳态产能的数学模拟器，计算分析找到了最优无量纲导流能力与裂缝穿透比之间的新型关系曲线，它是水力压裂优化设计的基础； 5 阐述了水力压裂油藏工程优化设计的重要性，提出了优化设计方法，在已知支撑剂物性参数条件下可简洁计算最优裂缝尺寸； 6 数学模拟给出了垂直裂缝井产量递减标准曲线，在井底定压条件下通过渐近分析表明，该递减曲线满足指数关系式。

By regression analysis of the obtained data, a relationship has been found between the bath depth and ingot height, which can be expressed by an exponential function, h(0,Y)=A e-B/Y, where A is the asymptotic value of the exponential function (when Y→∞hmax=A), B is a shape coefficient of the curve.

通过对已得数据的回归处理，找出了熔池深度h及锭高Y间的相关规律，得到h_(0，Y)=A·e_的指数函数关系，A是指数方程的渐近线，当Y+∞时h_(max=A是曲线形状系数。A和B均为重熔电流的函数，A=f_1，B=f_2，所以，h_(0，Y)=f_3。

Based on the analysis of the mechanism of robot manipulators, a trajectory tracking controlling research model is first built up with ADAMS, and its mathematical model is formulated through the study of robot kinematics and dynamics. After the modeling errors are analyzed in practical robotic systems, a conception of centralized error is brought forward according to the theory of weighting functions. In the case of modeling errors' exist, the robotic uncertain model is derived by introducing an auxiliary control variable into inverse dynamic analysis. The control strategy of robust exponential convergence is applied to the robotic uncertain model, the applicable conditions and the applicable controller with this application are presented. The stable control effect under three main model uncertainties (parametric errors, joint disturbs, joint frictions) are systematically studied on the previously built research model. The problems of robust exponential convergence controller which often results in unstable output and so produces a large relative error when the input trajectory is in a small range are resolved by adjusting the control parameters based on the controller's structure.

本文在机械手的机械结构分析基础上，利用ADAMS建立了用于机械手轨线跟踪控制研究的机械手模型；通过对机器人运动学和动力学问题的研究，建立了机械手研究的数学模型；分析了机器人系统中模型误差的主要来源，根据加权函数法分析，提出了模型集中误差的概念；在存有模型误差的情况下，采用逆动力学结构并引入辅助控制量，由机器人误差模型推导了机器人非确定性模型；提出了采用鲁棒指数收敛法对上述机器人非确定性模型进行鲁棒镇定的控制策略，并给出了对机器人进行鲁棒指数收敛控制时系统不确定因素应满足的匹配条件；针对机械手研究模型，深入研究了鲁棒指数收敛控制器对机器人系统中常见的模型参数误差、关节扰动、关节摩擦等不确定因素的镇定控制效果；针对鲁棒指数收敛控制器易产生控制量振荡的问题以及在小范围内系统轨线跟踪的稳态误差过大问题，本文分别提出了基于控制器结构的控制参数调整法和基于轨线跟踪范围大小的控制参数分段切换法。

The exponential model and double exponential model were the most practical and applied models for secondary clarifier simulation.

在二沉池模拟中，指数模型和双指数模型较为实用且应用较多。

Our main results are as follows: we have given a non-trivial estimate for a class of rational exponential sums,and the best possible upper bound for a class of characters sums with exponential functions.

我们的主要结果是：给出了一类有理指数和的非平凡估计，以及一类特征和的最佳上界。

After learning exponential function, constant regular meeting encounters a kind of problem that compares exponential type size.

学习了指数函数后，经常会碰到比较指数式大小的一类新问题。

There are two types of gold deposits in this area, namely altered rock type and quartz vein type.

本区金矿床包括两种类型：柴胡栏子金矿床为蚀变岩型金矿；莲花山和红花沟金矿床属石英脉型。

You were home and it was two weeks ago.

你回到了家里。当时是两周前。