查询词典 hilbert problems

Because the analytical solutions can be obtained in computations of elastodynamics problems, the considered problems become considerably simple and possess an evident generality, hence the deduction of self-similar solutions in other form has significance.

由于在弹性动力学问题的计算中可以获得解析解，使得考虑的问题相应地简化，并具有一定的普遍性，因此对自相似形式的解的推导具有重要的意义。

In this paper several problems in the elementary geometry, which seem simple but in fact need thorough analysis, are taken for example to explain how to make use of the knowledge learnt from the higher meths so as to study the problems concerning the eductional reform of the higher maths, which should lead to our consideration.

本文以初等几何中一些看似粗浅实际上需要深入分析的问题为例来说明，如何利用高等数学学到的知识，来研究中学数学等有关高师数学教育改革应引起大家思考的几个问题。

In 1970s, boundary value problems with equivalued surface are put forward. Andit is important to study them to solve practical problems. Li Ta-tsien and his partnersdo systematic research on them, especially study certain kind of elliptic boundary valueproblem with equivalued surface on the domain with thin layer.

二十世纪七十年代提出了一类等值面边值问题，它对于解决实际问题起到了非常重要的作用，李大潜等人对其进行了比较系统的研究，特别的对在具有薄层的区域上的椭圆型等值面边值问题进行了探讨。

At present, with China's ongoing social transformation some new problems arise, and to solve these problems we must further emancipate the mind.

当前，中国正在进行社会转型，出现了一些新的问题，要解决这些问题只有进一步解放思想。

Good health but some are prone to "wobbler" syndrome, heart problems, skin problems, hip dysplasia, and entropion - a folding outward of the eyelid rim, usually on the lower lid.

良好的健康状况但是有些常会有"摇摇晃晃"的症状，心脏问题，皮肤问题，臀部发育障碍，眼睑内翻－是一种眼皮向外翻，通常是下眼皮。

In these problems, the selection of international market entry mode is one of the most important problems.

其中，国际市场进入方式的选择问题是最重要的问题之一。

The main problems researched in the dissertation and achievements are as follows: The dissertation explains the science background and the theoretical and actual meaning of the task. The progress and the problems of the flow imaging technique are briefly explained. The advantages of electrical capacitance tomography are discussed. The paper discusses the formation and operating principle of ECT, and builds up the definite mathematical model by detail theoretical analyse, and establishes the Finite Element Model of the system by changing the finite boundary value problem of ECT into equivalence variation problem according to variation principle. On the basis of the FEM of the system, the paper builds the finite element model of the capacitance sensitivity field distribution and programs its finite element simulation software and proves the validity of the FEM of the ECT from different aspects. With the FEM and the qualitative analyse of the effect of each structural parameter of the capacitance transducer on its capability, this paper optimizes the structural parameters of the capacitance transducer, and obviously improves its capability. The compare of the simulated result with the static experimental result shows that the error of them is less than 0.9%.

其主要研究内容包括：阐述课题研究的学术背景及其理论与实际意义，概括总结出流动层析成像技术的发展现状和存在的问题，指出电容层析成像技术的优点；讨论电容层析成像系统的组成及工作原理，进行详尽的理论分析，以变分原理为基础，将ECT的有限元边值问题转换为等价的变分问题，从而建立系统的有限元模型；在系统有限元模型的基础上，建立敏感场的数学模型，编制有限元的仿真软件，并从不同角度证明电容层析成像系统有限元模型的正确性；利用有限元模型，定性地分析电容传感器各结构参数对其性能的影响，并对传感器结构参数进行优化设计，使其性能得到明显的改善。8电极ECT系统的仿真和静态实验结果的比较表明，它们之间的相对误差小于0。

The problems treated by the essentialism are relatively simple while the non-essentialism buries itself in endless problems.

前者处理的问题较为简单，后者却是将自己置于不尽的问题之流中。

Planar graphs also play an important role in colouring problems;to motivate such problems,let us return to our"road-map"graph,and let us suppose that Shell,Esso,B.

平面图在着色问题中还起着重要的作用；为了生动地说明这一问题，让我们回到路线图，并假定Shell、Esso、B。

Aiming at these problems, an expectation maximum based MAP algorithm is proposed and the performance is analyzed. The proposed algorithm avoids large matrix operations by using the EM algorithm to decompose the MIMO channel estimation problem into a series of single input single output problems. Besides, a joint estimation is carried out over multiple OFDM symbols in order to enhance the data transmission efficiency and the estimative performance of the proposed algorithm.

该算法利用EM算法把多输入输出信道估计问题化简为一系列独立的单输入输出问题，避免了大规模矩阵运算，降低了MAP算法的计算复杂度；为进一步改善MAP算法的数据传输效率及其估计性能，可通过对多个连续的OFDM符号进行联合信道估计。

Molecular Distillation is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products.

分子蒸馏技术是一种在高真空条件下进行的连续蒸馏过程，适合于分离高沸点、热敏性及具有生物活性的混合物。

They are to the Noughties what yuppies were to the Eighties .

那在六十年代是时髦的，但在八十年代肯定是过时了