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91.
Following Guin's approach to non-abelian cohomology [4] and, using the notion of a crossed bimodule, a second pointed set of cohomology is defined with coefficients in a crossed module, and Guin's six-term exact cohomology sequence is extended to a nine-term exact sequence of cohomology up to dimension 2 相似文献
92.
AI Jiang YE Ailun LIU Yuqiao 《Chinese Journal of Lasers》1998,7(6):501-504
1IntroductionSincethediscoveryofphotosensitivityingermanosilicateopticalfibersbyHiletal.in1978[1],significantprogreshasbeenma... 相似文献
93.
For modular group algebras over an arbitrary field we define new type of blocks: blocks with nilpotent extensions, and describe their source algebras. To do it, a general pattern is proposed for relations between the source algebra of a block and the source algebra of a block appearing in its decomposition in a suitable extension of the field of coefficients. 相似文献
94.
95.
Xiaochun Fang 《Proceedings of the American Mathematical Society》2006,134(10):3015-3024
Let be a unital -algebra, and let be a -dynamical system with abelian and discrete. In this paper, we introduce the continuous affine map from the trace state space of the crossed product to the -invariant trace state space of . If is of real rank zero and is connected, we have proved that is homeomorphic. Conversely, if is homeomorphic, we also get some properties and real rank zero characterization of . In particular, in that case, is of real rank zero if and only if each unitary element in with the form can be approximated by the unitary elements in with finite spectrum, where , , and if moreover is a unital inductive limit of the direct sums of non-elementary simple -algebras of real rank zero, then the above can be cancelled.
96.
Guillermo E. Villanueva Jesús Palací Miguel V. Andrés Pere Pérez-Millán 《Optics Communications》2010,283(24):5165-5168
A dual-wavelength fiber laser source based on two cascaded phase-shifted fiber Bragg gratings is presented. The gratings are written in an erbium-doped fiber, each configuring the cavity of a distributed feedback fiber laser. The spacing between lasing modes is controlled dynamically by the use of piezoelectric actuators. A continuous tuning range of 5-724 pm of the wavelength difference, which is equivalent to a photodetected 0.72-92 GHz range, is obtained. Efficient generation from the L to the W microwave and millimeter bands has been achieved by heterodyne photodetection of the dual-wavelength optical signal. 相似文献
97.
Exact stationary-wave solutions in the standard model of the Kerr-Nonlinear optical fiber with the Bragg grating
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By using dynamical system method to the standard model of the Kerr-Nonlinear optical fiber with the Bragg grating, under fixed parameter conditions, all possible exact parametric representations of the bounded stationary wave solutions are obtained from the double sine-Gordon equation. 相似文献
98.
T. Ohwada 《Functional Analysis and Its Applications》2006,40(2):151-154
Saito (Math. Proc. Camb. Phil. Soc., 117, 11–20, 1995) proved Sarason’s interpolation theorem for an analytic crossed product determined by a finite von Neumann algebra. We extend this result without the assumption that the von Neumann algebra is finite. 相似文献
99.
100.
C. Jesus P. Caldas O. Frazão J. L. Santos P. A. S. Jorge J. M. Baptista 《Fiber and Integrated Optics》2013,32(6):440-449
Abstract A fiber optic sensing system for simultaneous measurement of refractive index and temperature, based on a hybrid fiber Bragg grating/long-period grating arrangement is described. The experimental results show that this setup has a good performance in terms of linearity and sensitivity, the ratiometric output changes 4%/0.001 RIU and 3.6%/°C, respectively. The sensor resolution for the refractive index is ≈2 × 10?5 RIU. The simultaneous measurement of the refractive index and temperature was demonstrated. The sensing configuration has the ability to be read-out in reflection and works in the telecommunications window. 相似文献