查询词典 mal posed problem

After a further analysis based on the empirical results,a trial probe on the cognitiveprocessing mechanism of the problem representation of the word problem in two types of MLDwas made by the author.The MRD performed much poorer than the MLD only in the mostdifficult equation listing of word problem and the medium and most difficult problemrepresentation of word problem,which showed no difference in computation and comprehensionof simple meaning of the problem,but the gap between two types of MLD became wide as afunction of difficulty and cognitive loading.It indicated that the MLD only had some advantage over MRD for they used more cognitive skills to solve the problem.

基于以上实验的结果，对两类数学困难小学生的应用题问题表征的认知机制作如下推断：混合型数学困难学生仅在高难度水平的应用题列式成绩和中高难度水平应用题问题表征水平上比单纯型数学困难学生得分显著低下，表明两类数学困难小学生在计算能力与理解简单题意的能力上并无差异，但随着难度提高，认知负荷加重，两类数学困难学生在应用题解题上的差异得以突显，表明当需要运用更多的认知能力解决问题时，单纯型数学困难学生比混合型困难学生更具优势。

On the basis of the conversion relation of inverse matrix and adjoint matrix, by using 1/ω instead of |B'(xBx(subscript k|, a new Landweber iteration formula x(superscript δ subscript k+1)=x(superscript δ subscript k)-ωB'(x(superscript δ subscript k)Bx(superscript δ subscript kB'x(superscript δ kf(x(superscript δ subscript k)-y(superscript δ)is constructed for solving rank deficiency nonlinear least squares problem, with which the phenomenon that leads to ill-posed problem because the iteration matrix is rank-deficient and very ill-conditioned in numerical iterative process is avoided.

基于逆矩阵和矩阵伴随算子的换算关系，并用1/ω代替|B′(xBx(下标k|，构造出一个新的求解秩亏非线性最小二乘问题的Landweber迭代格式，x(上标δ下标 k+1)=x-ωB'(xBx(上标δ下标 k*B'x(上标δ下标 kf(x-y，从而避免了在迭代过程中由于迭代矩阵的秩亏和病态而产生的不适定现象。

In chapter 1, the relations between spectrum displacement problem and controllability, observabiity for linear systems over a commutative Banach algebra have been discussed, the open problem about spectrum displacement posed by Kaashoek have been solved, and the if and only if conditions for stability, stabiizabit~ detectability have been obtained.

第一章，讨论了交换Banach代数上线性系统的谱配置问题与可控性、可观性的关系，解决了Kaashoek等提出的关于谱配置的公开问题，给出并证明了判定其稳定性、可稳定性、可检测性的充要条件。

In this paper, we consider a Cauchy problem for the Laplace equation, which is a classical example of ill-posed problem.

众所周知， Laplace方程的Cauchy问题是不适定的，但这类问题在工程实践中有许多应用。

The basic idea of Tikhonov regularization is that linear compact operator equation of the first kind is replaced by the minimization problem of Tikhonov functional, the paper demonstrates the minimization of Tikhonov functional is an well-posed problem. In the end, the paper suggests a new type of iterative algorithm to solve inverse problems of parameter identification for one-dimension parabolic partial differential equation .

本文论证了Tikhonov泛函极小化问题是适定的，即满足西安理工大学硕士学位论文解的存在性、解的唯一性和解连续依赖于数据的稳定性：并且此极小化问题等价丁求解第一类方程的正规方程。

This paper discusses the conditional stability for solving the inverse sideways heat conduction problem by the rapid decreasing properties of the mollification kernel function, and obtain its regularization solution and its error estimate by constructing a well-posed problem.

利用磨光核函数在无穷远处的急降性质研究了反问题的条件稳定性，构造了一个适定的问题来逼近原问题，从而获得反问题的正则化解及其误差估计。

Many authors posed and discussed some boundary value problems,mainly the Dirichlet problem and mixed boundary value problem for second order elliptic equations with parabolic degeneracy.

许多作者提出和讨论了二阶退化椭圆型方程的一些边值问题，如Dirichlet边值问题和混合边值问题。

In chapter2 we obtain the constructure theorem and intechange theorem of 2-tournaments.wefind the correlation between the number of 3-cycles and 2-cycles in 2-tournament andits score vector,discuss a class of extreme value problem of tournament,answer partlya open problem posed by Brualdi.

第二章讨论了2-竞赛图和竞赛矩阵的一些基本问题：存在性和结构问题，证明了具有相同得分向量的任意两个2-竞赛矩阵可以通过三角形转换而互相得到，得到了2-竞赛图中2-圈与3-圈的数目与得分向量之间的关系式；讨论了2-竞赛中的一类极值问题，部分地回答了Brualdi〓的一个问题。

The electromagnetic inverse scattering problem governed by the fiest kind of Fredholm integral equation is an ill-posed problem.

摘要由第一类Fredholm积分方程所描述的电磁逆散射问题是非适定问题。

Paul Erds once posed the following problem about real line R: is it true that, for every infinite set X, there is a closed set E with positive lebesgue measure such that E doesn't contain any subset similar to X (I.e., there is no subset of E, which is a linear homeomorphic image of X). In 1984, K. J. Falconer proved the following: for a decreasing sequence of positive numbers {xn} such that \%lim\%xn=0 and \%lim\%(xn+1)/=1, Erds problem has a partial positive answer.

叶盛 Paul Erds曾提出如下关于实直线R的问题：是否对R的每一个无限子集X，都存在一个具有正测度的闭子集E，使得E的任何子集都不相似于X(E的任何子集都不与X线性同胚)。1984年，Falconer证明了如下结论：对于一个满足limxn=0和lim(xn+1)/=1的单调递减的正实数列{x n}，Erds问题有一个部分肯定的解答。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。