层

Characteristics of Lamb wave propagation in multilayered composite plates are influenced by many factors, the most important of which are: constituent properties, thickness and fiber orientation, the number of layers, and lay-up sequence and the direction of wave propagation.

层状各向异性板中Lamb波的传播特性受许多因素的影响，其中最重要的影响因素是：组层材料的性质、厚度以及纤维的方向、层数、层序、Lamb波传播方向。

The invention relates to distributivity phoneme communication system and network connecting method applied in residential district. It includes management layer, middle layer, and user layer. The management layer includes center monitoring controlling main engine and supervisor used to monitor, control, and supervise the whole system.

可应用于住宅小区的分布式语音通讯系统及网络连接方法，包括管理层、中间层和用户层；管理层，包含中央监控主机和管理机，负责整个系统的监控与管理；中间层，包含门口机，作为管理区域的辅助划分管理单位；用户层，包含用户机，负责与住户的交互。

In some embodiments, a graded semiconductor buffer layer is located beneath the buried oxide layer, while in other a doped semiconductor layer including Si doped with at least one of B or C is located beneath the buried oxide layer.

在一些实施方案中，渐变半导体缓冲层位于隐埋氧化物层下面，而在其他实施方案中，包含掺杂有B或C中至少一种的Si的掺杂半导体层位于隐埋氧化物层下面。

For each layer-divide symbol appeares regularly in weave diagram, the layer-divide symbol is affirmed first,then the attribute of each yarn and weft is fixed,the weave of each layer is analyzed at last. As to leno fabric, the reverse side of the fabric should be analyzed, tell the crossing warp from normal warp before drafting the looming draft.This paper introduces the method to analyze this kind of complex fabric through above two examples.

对四层织物分析时，找出组织图上有代表性的组织点的属性，因分层符号在组织图上出现时很有规律，可以先确定各层分层符号的位置，进而确定各根经纬纱的属性，分出各层织物，最后分析各层的组织；纱罗织物分析时，应分析织物的反面，先要区分出绞经和地经，然后才能绘出组织图。

During this stage, the cells group into three layers, the first is the 'ectoderm' which then in turn generates the 'mesoderm' and 'endoderm' layers.

在这一阶段，细胞分化为3层，第一层是"外胚层"，它最终会形成中胚层和内胚层。

The theoretical results demonstrates that the mechanical transfer characteristics of double coating depend on the relative magnitude of elastic modulus between cladding and buffer under the small radius approximation compared with the model of single coating.

理论研究表明：在小半径近似条件下，双涂层光纤的力学传递特性决定于涂覆层和缓冲层的弹性模量的相对值；当缓冲层的弹性模量远大于涂覆层时，其作用可忽略。

A typical representative of such a polymetal layer printing master blank contains a steel plate whereon a copper layer (7 to 10 μ thick) and a chromium layer (2 to 3 μ thick) with mat aspect are electrolytically deposited, which chromium layer in its turn is coated with the photosensitive coating suited for preparing the resist.

1991年参加过多金属层印刷主空白的典型代表，包含了钢板地上一铜层（7至10μ厚）和铬层（2至3μ厚垫方面）的电解沉积，反过来的铬层涂有准备的抵制适合光敏涂料。

"We proposed that the crust of Enceladus was composed of two layers: One, a surface layer of ice with carbon dioxide, and two, starting at no more than 3 kilometers, a mixture of icy clathrates that overlaid the core," Kieffer said.

"我们认为恩塞拉都斯卫星的壳是由两层组成的：第一层是含有二氧化碳的表面冰层，第二层是开始于不超过3公里深的包着核的冰笼混合层。"

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。

Roast a porcelain tooth to divide 2 F, most inside the layer is metal layer, in metal of inside the hull burn to knot the last porcelain cent and form the porcelain layer of outside.

烤瓷牙分两层，最内层是金属层，在金属的内壳上烧结上瓷分，形成外面的瓷层。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐