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Studies on basic working principles and designs of fiber lasersThe basic working principles as well as the major characteristics of laser and fiber lasers are firstly reviewed,including the interaction between light and matter, the laser oscillation conditions and the spectrum distribution,the gain characteristic and spatial hole burning effect,the influence of external environment on the stability of laser output and the actual limits of fiber laser bandwidth;The designs of bidirectional single-mode Er-doped fiber ring laser and multi-wavelength laser is then discussed,respectively;The characteristics of dynamic grating reflection spectrum of the fiber saturable absorber is systematically analyzed.?

在激光型光纤传感器的设计、实验现象的理论解释等方面做了如下的研究工作：光纤激光器的基本原理与设计方案概述了激光和光纤激光器的基本原理，包括光与物质的相互作用，激光振荡的条件及频谱分布等激光产生的基本原理：掺铒光纤的增益性质，空间烧孔效应和外界扰动对激光输出稳定性的影响，光纤激光器的实际极限带宽等光纤激光器的相关知识；分别讨论了双向单纵模环形腔激光器和多波长激光器的设计方案；系统地分析了掺杂光纤饱和吸收体中形成的动态光栅的反射谱特性。

The location of reflection spectrum varies with the grating period (corresponding to the Bragg wavelength of FBG), thus, by changing the grating period, the reflection spectrum of SFBG can be shifted by one wavelength spacing or more.

通过改变光纤光栅周期(对应光纤光栅布拉格波长)到适当的值，使超结构光纤光栅谱位移一个或者多个波长间隔，级联多个波长精确定位的超结构光纤光栅，实现了波分复用信道滤波器的宽带滤波。

Gabor-ring is often used in texture feature extraction, but it is based on the assumption that texture is narrowband signal and can not applied to most actual textured images that have more than one center frequency in power spectrum. To overcome the limitation of existing method, an improved method is proposed. According to this method, Gabor filters are constructed in accordance with the spectrum feature vector of texture, and a relaxation parameter is used to determine the effect of difference filters so as to integrate the frequencies and phases into the process of extraction.

Gabor环（即在频率域成环形分布的Gabor滤波器组）常被用于提取图像纹理特征，但它是以"纹理是窄带信号"为基础的，实际的纹理图像并不能很好地满足"窄带信号"的假设，用一个中心频率来描述一种纹理对能量集中在多个频率点的纹理图像往往不能取得理想的效果，而根据频谱特征值向量构造Gabor环的改进方法，通过松弛因子的加入改变不同滤波器的作用强度，综合考虑了多频率多相位对纹理特征提取的影响。

The usual way to calculate the residual shock response spectrum of the base shock response is as follows: the time domain shock response of the base is calculated firstly, then the residual shock response spectrum of the base response is calculated.

冲击作用下设备安装基座响应的冲击余谱的一般计算方法是先计算冲击作用下设备安装基座的时域响应，再计算安装基座响应的冲击余谱。

The multi-degree-freedom equivalent model of INS bracket is also given and analyzed to improve the analysis precision. The dynamic response spectrum of this model is achieved by modal analysis and spectrum theory. The numeric formulas of time-domain response are deduced by residue theorem.

对于惯导减振支架的多自由度系统等效分析模型，则运用模态叠加法和谱分析理论得到响应的功率谱，根据留数定理推导了系统时域加速度动力响应的数值计算公式。

One cause is that little information of solid spectrum is available from experimental data, because the solid always appears ruleless broadband absorption and emission spectrum.

另外，目前处理固体光谱广泛使用的理论是晶体场理论，而晶体场理论只能对固体光谱给出定性的分析，而不能给出定量的解释。

Aiming at this problem,the concept of the second order power spectrum was proposed based on the characteristic of the amplitude tune with pe- riodical notch spectrum in thin layer and theoretically researched.

为此，从薄层振幅调谐具有周期性陷频谱特征出发，提出了二阶功率谱的概念，从理论上对薄层的二阶功率谱特征进行了研究，建立了薄层厚度与二阶功率谱极大值之间的对应关系，给出了利用二阶功率谱进行薄层厚度预测的理论依据和方法，即根据薄层厚度和二阶功率谱的能量关系制作二阶功率谱图，图上强能量团对应的时间即为薄层时间厚度。

Then it analyzes the unstable and stable signals by applying Short Term Fourier Transform , Wavelet Packet Auto-Regressive Model Spectrum , the Second Order Cyclostationary Spectrum as well as chaos-fractal theory, extracts the fault features of analysis objects.

采用了短时Fourier变换、小波包AR谱、二阶循环谱方法及混沌分形理论分析了稳态和非稳态振动信号，提取出了分析对象的故障特征。

We discuss the segmental spectrum in order to further investigate the relationship of the segmental spectrum and structure.

在此基础上，进一步探讨了筛选出的光谱片段区与结构之间的关系。

Spatial spectrum estimation algorithm source code, spatial spectrum estimation array signal processing is an important element.

详细说明：空间谱估计算法源代码，空间谱估计是阵列信号处理的一个重要内容。

Nowadays, most of research are to build a transmutative Petri Nets through adding controlling place sets, controlling arc sets and controlling policy to the basic Petri Nets, while the Controlled Petri Nets could be used to argue many controlling theory problems conveniently and to induce many logically and physically supervisory and solve the Event Feedback Controlling Problems and State Feedback Controlling Problem in DEDS supervisory theory.

目前大多数的研究表现为在变形后的受控Petri网基础上，利用各种方法求得各种逻辑型、结构型控制器，解决DEDS监控理论中的事件反馈控制问题与状态反馈控制问题。

On one hand, there are discussions with the works council and union about extension of short time working up to the end of September.

一方面，有讨论，工程理事会和联盟关于延长工作时间短至9月底。