查询词典 unstable solution

Beginning with some cases, the article gives basic definitions of inverse problems and ill-posed problems. Then it discusses the Moore-Penrose generalized solution and the Moore-Penrose generalized inverse, and makes a conclusion that linear compact operator equations are ill-posed, that is, the Moore-Penrose generalized solution is unstable.

本文从一些实例出发，介绍了反问题和不适定问题的基本概念，并讨论了方程的Moore-Penrose广义解和Moore-Penrose广义逆，得出了线性紧算子方程的不适定性，即Moore-Penrose广义解的不稳定性的结论。

It is proved that the two-dimensional non-hydrostatic Boussinesq equations on the x ? z plane with the kinetic viscous term and the thermal dissipative term are unstable equations in the C 2 function class.2. If we replace the influence of the kinetic viscous term by Rayleigh friction and the thermal dissipative term by Newton cooling, the new generalized equations are stable equations in the C 1 function class. The construction of the solution space and the discriminating method for well-posedness of the problem of determining solution are given.

本文的主要结果如下：1证明了在y方向上均匀的带有运动粘性项以及热耗散项的两维非静力、Boussinesq近似的x-z面上两维旋转流体的控制方程组在C 2函数类中是一个不稳定的方程组。2如果以瑞利摩擦来代替粘性的影响，以牛顿冷却来代替热量的耗散，则所获得的一个新的方程组在C 1函数类中是一个稳定的方程组，给出了其解空间的构造和各种定解问题的适定性的判别方法。

However, the time-delay has no essential effect on the periodic solution and unstable solution.

而油膜力时滞对于系统的稳态同步周期解和失稳解，则没有本质影响。

In the process of analytical solution, the divergent item can be give up according to the physical meaning of the solution. But there is no chance to give up the divergent item in the step-by-step integration method. This is why the numerical solution is unstable.

在比较了含有此发散项的该通解的数值结果与平均常加速度法的计算结果后，发现它们是一致的，从而找到了逐步积分法不稳定的原因，即逐步积分法不能避开方程解集中的不稳定子集（从而导致了一种发散性的不稳定）。

Firstly, the integral-differential equation described the radiation field evolution is derived, and then the instability of its solution is also investigated analytically. By using the perturbation and iteration method, the threshold detuning and threshold linear growth rate of the unstable solution are analyzed and discussed in detail.

首先，建立了一个描述辐射场演化的积分一微分方程，解析分析了系统解的不稳定性，并采用线性方程解的微扰迭代方法进一步对系统不稳定解出现的失谐量阈值和线性增长率阈值等作了详细讨论。

SVM is a new and outstanding learning machine and is an efficient machine-learning tool in dealing with small samples.SVM overcomes some shortcomings of neural network,such as slow convergence,unstable solution,and bad generalization ability.

支持向量机是由Vapnik等人于上世纪90年代提出的一种崭新的学习机器，它作为统计学习理论的实现方法，是处理小样本学习的有效工具。

Unstable solution that may exist in SIRT or SART which converges to the Solution of a least-square problem is avoided.

阻尼代数重建技术，这种方法收敛于阻尼最小二乘解，因而克服了收敛于最小二乘问题的SIRT、SART法可能出现的不稳定解。

A nonlinear evolution equation for the radiation field in magnetically insulated transmission line oscillator is derived and the threshold conditions of the nonlinear unstable solution are studied.

导出了磁绝缘传输线振荡器中辐射场的非线性演化方程，并讨论了在临界值点附近可能出现非线性不稳定解的条件。

The method is called apparent density inversion. The inversion technique overcomes drawbacks of long computation and unstable solution, it takes less than 20 seconds to compute a density data set of 128 ×128×10 points on a PC of 1.99 GHz. The method is demonstrated on synthetic models and on real gravity data

本反演方法克服了传统已有方法计算时间特别长、解稳定性差的缺点，在主频1.99 GHz的微机上，反演128×128×10个密度值的计算时间小于20 s，理论模型和实际资料的应用表明反演具有较好的效果。

To obtain a complete picture about shock formation in non-viscous flow, in the succeeding chapter we investigate the isothermal shocks in adiabatic flows. We find that in this case the shock solution still exists, but the structure and the properties of the solution are greatly different from above even qualitatively. In some region of the parameter space there only exists unstable shock solution and in some region of the parameter space there may exist two stable shock solutions.

为得到完整的无粘流体中激波形成的图象，在接下来的第四章，我们研究绝热流体中等温作为激波条件时的情况，发现此时激波解仍存在，但解的结构和性质甚至在定性上都与前两章有了显著的不同：某些参数空间只存在非稳定的激波解，某些参数空间则会同时出现两个稳定的激波解。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。