查询词典 quasi-definite

The alternative estimators used in this paper include least squares estimator, stratified weighted least squares estimator, probability weighted least squares estimator, and Quasi-Aitken weighted least squares estimator.

中文摘要抽样调查设计随著资讯需求的增加日益复杂，然若参数的估计方法无法配合所使用的抽样调查设计，则统计推论结果将难以达到预期的精确度。

Sufficient conditions for existence of positive periodic solutions of these systems are established and we investigate a stochastic Lotka-Volterra ecosystem, by use of the mixed quasi-monotone theory and Liapunov function method, some new results are obtained.

最后，我们研究了n种群随机Lotka-Volterra生态模型，利用混合单调流理论和It〓型随机微分方程知识，得到了其解过程的均方渐近稳定性和强生态稳定性的结果。

In Chapter 4, using the formula A_k(2) given by Wei, we propose a new A_k(2)-SQP method, which develepments the using of the quasi-Newton formula BFGS, and combines with SQP method to solve constrained optimization problems, the corresponding algorithm possesses global convergence and supei linear convergence property.

第四章，利用韦提出的A_κ(2)公式，我们给出了一种A_κ(2)-SQP方法，该方法把拟牛顿修正公式BFGS进行了推广，并结合SQP方法去解约束优化问题，相应的算法具有全局收敛性和超线性收敛性。

There have been a lot of studies this aspect when the exact solution u∈H~2 or u∈H~3. [4], [52] and [50]studied the convergence of conforming linear triangle elements with minimal regularity assumptions u∈H~4, here u is the solutions of the second order elliptic problems. However, their is another vital deficiency of the previous studies, i.e., they relies on the regularity assumption or quasi-uniform assumption on the subdivision of meshes.

对二阶问题，构造了一个新的单元格式，当其精确解具有低正则性时，在不要求网格满足正则假设或拟一致假设的条件下，我们得到了最优误差估计，与[33]相比，我们的证明方法较为简单；对于Stokes问题，研究五节点非协调矩形元对它的逼近，通过引入全新的估计方法，给出了关于速度、压力的超逼近性质。

For the original infinite dimensional problem, if the inexact quasi-newton method with Broyden updating can not converge quickly , for example, it can not attain super linear convergence rate , then when the discretization is becoming finer and finer , we can not get fast convergence rate for the corresponding finite dimensional problem.

对于原来的无限维问题，如果使用不精确Broyden方法不能得到较快的收敛速度，比如超线性收敛性，那么当离散化逐渐加细的时候，对于所得的有限维问题使用不精确Broyden方法也不可能得到较快的收敛速度，所以有必要在无穷维空间上对收敛性问题加以分析，从而为不精确拟牛顿法结合投影法求解算子方程做好准备。

For this new definition of quasi-sliding mode its stability problem is proved meanwhile the linear switching function is determined.

对新定义的准滑动模态，解决了其稳定性并给出了切换函数。

The paper has proposed the concept and the analysing method of quasi-symmetrical array, so that the order of linear equations is reduced by half.

提出准对称阵列的概念及分析方法，将上述线性方程组的阶数降低了一半。

According to the linear search technique, the Quasi-Newton algorithm can be divided into monotone algorithm and non-monotone algorithm.

根据所采用的搜索准则，拟牛顿算法可以分为单调的算法和非单调的算法。

In chapter three, quasi-newton methods are introduced, Wolfe-Powell and Armijo linear search are also presented.

这些在论文以后的各章节都要反复用到。

A simultaneous dual-wavelength continuous wave, quasi-cw or linearly polarized wave diode-end-pumped Nd:YAG laser operating at 1319nm and 1338nm is demonstrated. To the best of our knowledge, our experimental results achieve the highest level in the domestic domain. The simultaneous dual-wavelength laser provides an experimental basis for generating highly coherent THz wave radiation of 3.23THz by nonlinear optical difference frequency method.2. A diode-end-pumped Nd:YAG crystal, type-I critical phase matching LBO crystal intra-cavity frequency doubled, simultaneous multi-wavelength red laser at 659.5nm, 664nm and 669nm is firstly realized.

本论文主要围绕用于差频产生THz辐射源的多波长激光器及THz光子晶体的带隙特性分析而展开，论文的主要内容包括：一、从LD端面泵浦固体激光器的激光阈值公式出发，理论计算了腔镜对于两个波长的透过率关系，实现了LD端面泵浦Nd：YAG 1319nm/1338nm双波长激光连续、准连续及线偏振稳定输出。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

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。