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81.
平面圆形膜片式光纤布拉格光栅温度补偿压强传感 总被引:2,自引:0,他引:2
报道了利用光纤布拉格光栅反射波谱带宽展宽技术实现温度补偿的压强传感新方案。结合平面圆形膜片应变调谐的特点,采用膜盒式结构,将光纤光栅中心对准平面圆形膜片零应变半径并沿径向粘贴,利用反射波谱带宽对应变敏感而对温度不敏感的特性解调压强,成功地实现了温度补偿的压强传感测量。基于光谱分析仪0.05nm的光谱分辨力,实验测得带宽随压强响应灵敏度为0.34nm/MPa,压强精度为±0.15MPa,压强测量范围为0~7.5MPa。实验结果与理论分析基本一致。 相似文献
82.
83.
Pedro D. Alvarez 《Annals of Physics》2007,322(7):1556-1586
A particle system with a (2 + 1)D exotic Newton-Hooke symmetry is constructed by the method of nonlinear realization. It has three essentially different phases depending on the values of the two central charges. The subcritical and supercritical phases (describing 2D isotropic ordinary and exotic oscillators) are separated by the critical phase (one-mode oscillator), and are related by a duality transformation. In the flat limit, the system transforms into a free Galilean exotic particle on the noncommutative plane. The wave equations carrying projective representations of the exotic Newton-Hooke symmetry are constructed. 相似文献
84.
激光束照射到表面被粘污的反射镜上会产生干涉环,入射光束和反射光束在被粘污表面产生散射光干涉.随着入射角的变化,光束在反射镜玻璃片内光程改变,引起干涉环从中心冒出或缩进,干涉环级数的变化与入射角的平方成正比. 相似文献
85.
86.
Chemical imaging systems help to solve many challenges in various scientific fields. Able to deliver rapid spatial and chemical information, modern infrared spectrometers using Focal Plane Array detectors (FPA) are of great interest. Considering conventional infrared spectrometers with a single element detector, we can consider that the diffraction-limited spatial resolution is more or less equal to the wavelength of the light (i.e. 2.5-25 μm). Unfortunately, the spatial resolution of FPA spectroscopic setup is even lower due to the detector pixel size. This becomes a real constraint when micron-sized samples are analysed. New chemometrics methods are thus of great interest to overcome such resolution drawback, while keeping our far-field infrared imaging spectrometers. The aim of the present work is to evaluate the super-resolution concept in order to increase the spatial resolution of infrared imaging spectrometers using FPA detectors. The main idea of super-resolution is the fusion of several low-resolution images of the same sample to obtain a higher-resolution image. Applying the super-resolution concept on a relatively low number of FPA acquisitions, it was possible to observe a 30% decrease in spatial resolution. 相似文献
87.
88.
This paper presents a new class of valid inequalities for the single-item capacitated lot sizing problem with step-wise production costs (LS-SW). Constant sized batch production is carried out with a limited production capacity in order to satisfy the customer demand over a finite horizon. A new class of valid inequalities we call mixed flow cover, is derived from the existing integer flow cover inequalities by a lifting procedure. The lifting coefficients are sequence independent when the batch sizes (V) and the production capacities (P) are constant and when V divides P. When the restriction of the divisibility is removed, the lifting coefficients are shown to be sequence independent. We identify some cases where the mixed flow cover inequalities are facet defining. We propose a cutting plane algorithm for different classes of valid inequalities introduced in the paper. The exact separation algorithm proposed for the constant capacitated case runs in polynomial time. Computational results show the efficiency of the new class mixed flow cover compared to the existing methods. 相似文献
89.
On <Emphasis Type="Italic">l</Emphasis><Subscript>2,<Emphasis Type="Italic">p</Emphasis></Subscript>-circle numbers 总被引:1,自引:1,他引:0
W.-D. Richter 《Lithuanian Mathematical Journal》2008,48(2):228-234
Circle numbers are defined to reflect the Euclidean area-content and, for p ≠ 2, suitably defined non-Euclidean circumference properties of the l
2,p
-circles, p ∈ [1, ∞]. The resulting function is continuous, increasing, and takes all values from [2, 4].
The actually chosen dual l
2,p
-geometry for measuring the arc-length is closely connected with a generalization of the method of indivisibles of Cavalieri
and Torricelli in the sense that integrating such arc-lengths means measuring area content. Moreover, this approach enables
one to look in a new way into the co-area formula of measure theory which says that integrating Euclidean arc-lengths does
not yield area content except for p = 2.
The new circle numbers play a natural role, e.g., as norming constants in geometric measure representation formulae for p-generalized uniform probability distributions on l
2,p
-circles. 相似文献
90.
孔洞受压的统一极限分析 总被引:1,自引:0,他引:1
采用俞茂宏统一强度理论分别就平面应变和平面应力总是对受压孔洞进行了极限分析,得到了各自的统一解形式。以往的基于Tresca、Mises、双剪屈服准则以及Mohr-Coulomb强度理论的极限解均为本文统一解的特例。此解可以适应于广泛的不同性质的各灯材料,合理也得出不同材料的相应解。 相似文献