极小

In Chapter 2,a steady permeability identification problem in elliptic equa-tions for two-dimensional orthotropic medium is considered.We construct afunctional,obtain its first and second Gateaux differential,and prove that thefunctional is strictly convex on a convex admissible function set.We seek to iden-tify the permeability by minimization of the above functional.

第二章研究了二维稳态正交异性介质的渗透率反演问题，我们构造了一个泛函，求得该泛函的一、二阶Gateaux微分，证明了它在一个凸的容许集上的严格凸性，并使用极小化泛函即变分方法来求解此问题。

Based on the analysis, a new AFC system based on self-optimizing control is proposed with the experience of experts.

本文中简要分析锁相型自动频率控制系统的基本原理及其在实际应用当中遇到的问题，进而提出了一种新型的基于反射波极小值的AFC系统，并对其原理进行了深入的剖析。

In conic optimization one minimizes a linear objective function over the intersection of an affine space with a regular cone in finite dimension.

它指的是在一个仿射空间与一个正则锥的交集上，求线性目标函数的极小或极大值。

Linear constraint particle swarm optimization algorithm is a global optimization dealing with constraints of non-negative and affine real space.

粒子群算法虽有全局优化性能，但也会陷于局部极小，且缺少约束处理机制。

An implicit Curve reconstruction method is proposed which represents the curve with all algebraic tensor-product B-spline,and minimizes the tension ofthe B-spline and the approximate geometric distance between the curve and the point set.

提出一种以代数张量积样条曲线作为几何表示形式，基于近似几何误差和薄板能量极小化的隐式重构模型。

In order to solvepiecewise algebraic varieties, we propose a new method to compute an algebraic varietyon a convex polyhedron by adding hyperplanes with the method of Groebner bases. Thus,the algebraic variety on the convex polyhedron is transformed to the positive solutionsof a system of polynomials. Besides, the minimal decomposition is also obtained.

通过添加超平面技巧将Groebner基方法应用到凸多面体内任意维代数簇的计算上，从而把凸多面体内的代数簇转化为另外一组多项式方程组的正解，并且得到了该代数簇在凸多面体内的极小分解。

It indicated that the annual runoff of the main and tributary of the Yarlung Zangbo river had an obvious decline trend during 1960s and reached the minimum in 1980s, since then, the annal runoff increased and a relatively wet season occurred in 1990s.

同时研究还发现，雅鲁藏布江干支流在20世纪60年代左右径流量较大，但在进入60年代中后期之后，年径流量呈逐渐减小的趋势，这种趋势在80年代附近达到极小值，此后径流量逐渐回升，并在90年代后逐渐进入相对丰水期。

By the process of numerical control machining ,carrier antrum of high quality is made out,and the efficiency is improved.

介绍了采用高速数控雕铣机床加工一种尺寸极小、精度要求较高的有色金属零件，利用数控加工的一般流程，体现了高速数控加工的突出特点，加工出高品质的微波芯片零件，大大提高了其加工效率。

Large catches of alates may be trapped in areas where the aphid population in the field is extremely small.

在蚜群极小的田间可诱捕到较多的有翅蚜。

In energy regions far away from a minimum, effective mass can be negative or even approach infinity .

在远离极小值点的区域，有效质量可能为负值甚至趋于无穷大。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。