谱几何

It obtains that the transport operator A has no complex eigenvalue s,and the spectrum of the transport operator A consists of finite real isolated eigenvalues which have a finite algebraic multiplicity in trip Pas.

本文研究了板几何中一类具各向异性、连续能量、均匀介质的迁移算子的谱，得出了该算子A在带域Pas中无复本征值和由有限个具有限代数重数的实离散本征值组成等结果。

The relation between the spectrographic aperture ratio and elliptical eccentricity, spectral angle is also analyzed according to the elliptical geometry, it will decrease when the x-ray wavelength increases.

根据椭圆的几何关系，研究了光谱相对孔径与椭圆的离心率和谱线探测角之间的关系，它随X射线波长增大而减小。

The geometries,electronic structures,polarizabilities and hyperpolarizabilities,as well as the UV-Vis spectra of the two organic dye sensitizers containing bis-dimethylfluorenyl amino benzofuran were studied via density functional theory and time-dependent DFT.

运用密度泛函理论和含时密度泛函理论研究了两种含二-二甲基芴氨基苯并呋喃基团的有机染料敏化剂的几何结构、电子结构、极化率和超极化率以及紫外可见谱。

This paper mainly study the relations between some algebraic properties of Roe algebras and the coarse geometry of metric spaces, and its applications to the reduced crossed product C-algebras and the coarse Baum-Connes conjecture.

本文主要研究这类C~*-代数的某些性质与底空间几何之间的联系及其在交叉积C~*-代数和粗Baum-Connes猜测中的应用。第一章研究交叉积C~*-代数的Schwartz型谱不变子代数。

The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

When 2 events occur within a same focal region and the distance between 2 events is far shorter than the distance between events and the station, the ratio of observed spectral amplitudes of the direct P and S phases is linearly correlated with the ratio of their radiation pattern factors, and radiation pattern factors depend on geometrical property focal mechanisms.

发生在同一震源区的两个地震，当地震之间的距离远小于地震到台站之间的距离时，同一个台站的直达P波、S波零频观测谱值之比与其辐射图型因子之比线性相关，而辐射图型因子取决于震源机制解的几何特性。

On the aspect of error compensation, the system using the geometric average sound pressure instead of the arithmetic average sound pressure to get the sound pressure of the measurement point. This method not only reduces the high frequency error in the sound intensity measurement, which compensates the finite difference approximation error, but also greatly reduces the computation of the sound pressure spectrum.

误差补偿方面，课题采用几何平均声压代替通常的算术平均声压来计算双传声器法的声场声压值，这样不仅可以有效的减少声强测量中的高频误差，对有限差分误差起到了补偿作用，而且还大大减小了声压谱计算中的计算量。

From the point of view of geobotany, with the method of correlative factors of growth of plants, a countrywide theoretic ecological division was done for the introduction of Camptotheca acuminata and three kinds of areas of ecological preferent zone, ecological adaptive zone and ecological unadaptable zone were divided. With the theory of synecology, the characteristic on environment, constitution, life form spectrum, diversity, similarity of plots of communities were researched. Applying the method of species association, discrete distribution, indensity index, fractal geometry, etc. to research relations between the species of the communities, space distribution of Camptotheca acuminata, structure of age of Camptotheca acuminata, in different communities. Using the theories of autoecology, distibutons of seeds on land and growth of seedlings in vertical and horizontal directions, biomass of organ of Camptotheca acuminata were analyzed. On the opinions of conservation biology, the external and internal factors impressing Camptotheca acuminata were analyzed to research the mechanism of the endangered species, and with using of CTM Model, the future development direction of Camptotheca acuminata in different communities were forecasted, and. Standing on the position of resources ecology, discussing the regularity of camptothein in Camptotheca acuminata of different sites and seeding of different resources, also the the derive technics of camptothecin.

本文从地植物学的角度，运用植物生长相关因子法，对我国喜树资源的生态适宜区进行了划分，理论上确定了我国的喜树的引种栽培的最适生活区域、生态适宜区域和不适宜生活区域；从群落生态学的角度，对野生喜树所在的典型群落的群落环境、群落组成、群落生活型谱、群落的物种多样性特点、群落样地间相似性进行了研究；从种群生态学的角度，运用种间联结性、离散分布模型、聚集强度指数、分析几何等分析手段，对野生喜树所在典型群落间的种间关系、喜树的空间分布格局、年龄结构等进行了分析；从个体生态学的角度，对不同年龄组的喜树的种子的散落的垂直分布、水平分布、时间分布及种子发芽率和千里重等特点、不同种源的人工喜树苗期特点、喜树的高生长和茎生长特点、喜树的器官生物量特点进行了研究；从保护生物学的角度，对野生喜树的濒危的内部因素和外部因素进行了探讨，并运用CTM模型对不同群落中野生喜树的种群趋势进行了预测；从资源生态学的角度，对我国地理环境下喜树中喜树碱含量的地理分布规律、不同种源的喜树幼苗中喜树碱含量变化规律进行了研究，并对喜树碱的提取工艺进行了探讨。

The general formulae are constructed for studing the geometric anisoplanatism of an adaptive optics by the transverse spectral filtering method.

利用横向谱滤波方法给出了研究自适应光学几何非等晕性的一般关系式。

The x-y spatially-resolved mapping of polarized Raman scattering spectra from a single tetrapod-like ZnO nanostructure were proposed and performed, with different polarized scattering configuration by utilizing the intrinsic geometry configuration.

此外，通过对量子线的磁阻测量，揭示一维结构中载流子在磁场中的输运行为。 2。首次根据四角晶须状ZnO纳米结构的天然的空间几何构型，采用不同的Raman散射配置，研究单个纳米结构的具有高空间分辨率的偏振Raman二维扫描谱。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。