波

In this paper,finite-difference time-domain method was used to calculate the driving-point impedance of radial disk in circular groove guide.

引言圆形槽波导是一种新型波导，和传统波导相比，具有低损耗、高功率容量、低色散和宽频带等优良特性。

To investigate the characteristics Of irregular wave force on circular cylinder near the bottoms ,a series of measurements have been carried out in wave tank .

本文旨在探讨置於底床附近之水平柱体所受之不规则波力，并在波浪水槽内进行，系列之模型试验以了解波力特性、波力数与周期参数、底床问距比之关系。

1Niche construction can lead to stable coexistence of diverse genotypes in spatially structured population, which supports a stable polymorphism even without heterozygote superiority.(2)With habitat deterioration, niche construction accelerates the formation of steady polymorphism and hence impedes the harmful influences of environment on the population, which might embody a life-history strategy of organism under the unfavorable environment.(3)Niche construction results in the coexistence with alternative polymorphism through genotype-environment feedback and limited gene flow.(4)The niche-constructing organism is an active force to alter its environment and hence the direction of natural selection in order to better survival.(5)Spatial dynamics and distribution pattern of metapopulation are profoundly influenced by time-lagged niche construction.(6)Metapopulation size can reach a fixed level in the recency effect and equal weighting of time lag but is statistical stability in primacy effect, which implies the primacy effect is most remarkable.(7)The increment in the relative weightingof each generation\' niche construction and the length of time lag are significant factors for system destabilization.(8)Moderate capacity of positive niche construction benefits the metapopulation persistence.(9)The narrowing of niche breadth can decrease the metapopulation size and thereby increase the extinction risk.(10)The coupled function of time lag and niche construction make the system oscillation and generate the spiral wave, spiral-broken and circular wave in heterogeneous habitat.The spatial distributions of metapopulation and resource content are complementary due to a phase lag of their both frequencies.(12)Metapopulation persistence with niche construction depends not only on the balance between colonization and extinction, but also on the balance between the ability of niche construction and natural dissipation of habitat.(13)Metapopula-tion can survive under certain condition when the percent of suitable patches in habitat is lower than the ration of extinction to colonization.(14)Two thresholds exist in the process of transition of habitat quality dynamics from unsuitable to suitable, which include the intensity of niche construction and the initial condition of system.(15)Metapopulation size is positive correlated with the ability of positive niche construction, which means that organism or population who has strongly positive influences on their environment plays an important role to maintain the available habitat.

通过上述几个方面的研究，主要得出以下15条结论：(1)生态位构建可使空间结构种群，甚至是在没有杂合子优势的条件下，形成多种可能的稳定基因型分布模式；(2)随着环境的破坏与恶化，种群的生态位构建作用加速其较早形成稳定多态以阻碍环境对种群的不利影响，解释了有机体在不利环境下的一种生活史对策；(3)生态位构建作用通过基因型—环境反馈机制及有限的基因交流导致基因型多态的稳定共存；(4)有机体的生态位构建作用是一种积极的动力改变环境进而改变其自然选择的方向；(5)生态位构建的时滞作用对集合种群动态和空间分布产生深刻影响；(6)集合种群大小在时滞的崭新效应和等权重效应下达到一固定值，而在首位效应下达到统计稳定，表明首位效应的影响最显著；(7)首位效应下生态位构建相对权重的增量和时滞的长度是影响系统不稳定性动态的关键因素；(8)适中的生态位构建强度有利于集合种群的续存；(9)生态位宽度变窄会减少集合种群的数量从而增加其灭绝风险；(10)时滞和生态位构建的双重作用使系统产生周期振荡，并在异质性环境中产生稳定的螺旋波，破碎的螺旋波和环形波三种分布模式；(11)集合种群与资源含量的空间分布因为相滞而互补；(12)具有生态位构建的集合种群续存不仅取决于侵占率与灭绝率之间的平衡，而且依赖于生态位构建能力同其生境的自然消耗速率之间的妥协；(13)当生境中适合侵占的斑块比例小于其侵占率与灭绝率之比时，生态位构建作用促使集合种群在一定条件下续存：(14)生境斑块的状态从不适合到适合转变过程中存在生态位构建强度和系统初始条件这两个阈值；(15)集合种群的大小同正生态位构建能力正相关，意味着对环境具有较强正作用的有机体对维持有效生境起积极作用。

It is defined that the two integrating ways' characteristics of the wavelet NN and theirs applying on the equipments' intelligence diagnose. Wavelet analysis technology has the ability of analyzing strongly the non-placidity signals' time-frequency, self-studying the NN, of dealing with data distributed and collaterally, of mapping non-linear ability, and it is fit for diagnosing failures.

利用小波分析对非平稳信号强的时频分析能力和神经网络的自学习、分布式并行处理数据及非线性映射能力，以及它们适合于故障诊断的特点，说明小波与神经网络的松散型和和紧致型结合途径下产生的两种小波神经网络的各自特点及其在设备智能诊断中的应用。

With enough free-surface range and collocation point number, this paper discusses the effects of the two kinds of distances on the numerical convergence, proposes the expressions for the inner distance, and has obtained consistent and convergence results.

本文研究了潜水椭球和Wigley船型的兴波问题和绕射问题，计算了非线性的兴波阻力系数、纵向一阶波浪扰动力和二阶倍频波浪扰动力，以及兴波武汉理工大学博士学位论文波形和绕射波形。

At last, guided by the theoretical calculation mentioned above, a series of experiments were carried out. The wavefront distortion of a plano concave lens was measured. The total error was less then 8%. This certified the measured results of the interferometer. The wavefront distortion of a one-side pumped zigzag slab gain medium in different pumping power was measured.

最后，在上述理论计算的指导下，进行了一系列波前检测实验：对一个焦距已知的平凹透镜所产生的波前畸变进行了检测，总的测量的误差小于8%，验证了系统测量结果的准确性；测量了一个单侧泵浦的之字形板条增益介质，在不同泵浦功率下的波前畸变情况。

We establish a new observation model of α-stable distribution for low altitude detection. It is very concernment that fractional lower-order statistics based detection and estimation robust approach for radar target signals, so as to perform optimal detection under constant probability of false alarm.

在不同的海况下，由于雷达波在波峰和波谷间的反射以及在波浪边缘的绕射等复杂电磁现象，使得雷达波不仅频谱形状不规则，而且反射单元的概率分布也超出常规，所以必须高度重视海杂波的特性研究，从中找出有价值的参数。

The results show that the frequency characteristic corresponds with vortex structures; the detail and approximate characteristics of signal are reflected by wavelet coefficient at different scales; the coefficient map of continuous wavelet transformation reveals the self-similarity of the signal.

采用傅里叶变换和小波变换技术，实现了混合层密度脉动信号的频谱与多分辨率分析，结果表明：信号的频域特性与流场的涡结构相对应，不同层面的离散小波系数反映了不同尺度下信号与图像的细节和平滑近似特征，连续小波变换系数图定性的反映了信号的自相似特征。

Take the method of "subarea" and "conjunction" to segment the whole request model to three parts. Making use of boundary continuousness between medium and lining structure at stress and displacement, construct a wave function that can satisfy the stress boundary condition at horizontal surface by the scattering of SH-waves in circular part. And then, availing of the wave function, conjoin the circular part into the semi-circular hollow space at common boundary. The problem can be reduced to solve the question that can only meet the condition of "conjunction". Finally, the solution of the problem can be summarized to a series of algebraic equations and solved numerically by truncating the finite terms of the infinite algebraic equations.

采用"分区"与"契合"的方法，将整个求解区域分割成三部分，利用介质与衬砌结构在边界上的应力、位移的连续性，构造一个可以自动满足水平界面上应力边界条件的圆域对SH波散射的波函数；再利用这一波函数将圆域与半圆形凹陷半空间的"公共边界"进行"契合"，将问题简化成对一个只需满足'契合'边界条件的散射问题的求解；最终归结为对一组无穷代数方程组的求解问题，利用截断有限项的方法对其进行计算。

In addition we establish a new moving coordinate system in the neighborhood of the wave front and obtain a revised eikonal equation describing the curvature effect of waves in the usual orthogonal coordinate system.

由此我们获得了二维和三维情形下靶型波的具体形式。对三维涡卷波和V-形波，我们也给出了它们的具体形式。在第四章，我们应用摄动方法，较简捷地获得了组织中心沿径向和轴向的运动规律。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。