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991.
单模光纤陀螺正交锁相检测方法的研究 总被引:3,自引:0,他引:3
研究了用于干涉型单模光纤陀螺系统的正交锁相检测方法,采用双参考信号,使输出的信号与噪声分离,不仅提高了光学系统信号的信噪比,同时可以引入移相反馈控制,大大减小了系统的漂移,系统的零点漂移已达到0.2deg/h。 相似文献
992.
We explore the consequences of certain commutativity hypotheses on a single nilpotent element or the set N of all nilpotent elements. We give several sufficient conditions for N to be an ideal. We present some nontrivial examples, including an example in which N is commutative (in fact, N
2 = {0}) and N is not an ideal.
Received: April 27, 2006. Revised: July 31, 2006. 相似文献
993.
W. Mader 《Combinatorica》1995,15(4):533-539
For every positive integerk, there is a positive integerf(k) such that every finite digraph of minimum outdegreef(k) contains verticesx, y joined byk openly disjoint paths. 相似文献
994.
J. Arthur 《Il Nuovo Cimento D》1996,18(2-3):213-220
Summary The use of synchrotron radiation to excite low-lying nuclear resonances is a rapidly developing field showing great promise
for hyperfine spectroscopy, phonon spectroscopy and kinetic studies, crystallography, and fundamental physics experiments.
Recent technical advances in synchrotron sources, optics, and fast detectors have drastically increased signal rates and expanded
the range of samples that can be studied. A typical experiment today uses a high-brightness synchrotron source having X-ray
pulses well-separated in time, a meV-bandpass monochromator using perfect crystals of silicon or germanium, a sample containing
resonant nuclei, and an avalanche photodiode timing detector. Both coherent and incoherent scattering can be observed; the
coherent scattering is used for hyperfine spectroscopy and studies of diffraction interference phenomena, and the incoherent-scattering
signal promises to be very useful for phonon spectroscopy and other studies of excitations in condensed systems. At this point
seven nuclear isotopes have been used to resonantly scatter synchrotron radiation, but the number is rapidly increasing.
Paper presented at the ICAME-95, Rimini 10–16 September 1995. 相似文献
995.
László Erdős 《Letters in Mathematical Physics》1993,29(3):219-240
The ground-state density of the Pauli operator in the case of a nonconstant magnetic field with constant direction is studied. It is shown that in the large field limit, the naturally rescaled ground-state density function is bounded from above by the megnetic field, and under some additional conditions, the limit density function is equal to the magnetic field. A restatement of this result yields an estimate on the density of complex orthogonal polynomials with respect to a fairly general weight function. We also prove a special case of the paramagnetic inequality.Part of this research was conducted during the U.S.-Sweden Workshop on Spectral Methods sponsored by the NSF under grant INT-9217529. Partial support by NSF grant PHY90-19433 A02 is also acknowledged. 相似文献
996.
光束的空间相干性与空间质量评价 总被引:3,自引:2,他引:1
光束空间质量评价的标准应该能够反映光束的空间相干性和强度(功率或能量)分布,并主要由空间相干性的优劣来说明.本文对模式纯度(1-δ)以及空间质量评价因子-衍射极限倍数因子M2做了讨论,并对此因子的表达形式提出了我们的改进建议. 相似文献
997.
In this paper, a pendant to a recent survey paper, the authors discuss several open problems in categorical topology. The emphasis is on topology-oriented problems rather than on more general category-oriented ones. In fact, most problems deal with full subconstructs or superconstructs of the constructTop of topological spaces and continuous maps. 相似文献
998.
The paper is devoted to a question if the Levi property is preserved by direct sums and quotients. The three-space problem for the Levi and Lebesgue properties in topological Riesz spaces is also investigated. 相似文献
999.
Summary.
We prove convergence of a class of higher order upwind
finite
volume schemes on unstructured grids for scalar conservation laws in
several space dimensions. The result is applied to the discontinuous
Galerkin method due to Cockburn, Hou and Shu.
Received
April 15, 1993 / Revised version received March 13, 1995 相似文献
1000.
Hiroshi Iritani 《Mathematische Zeitschrift》2006,252(3):577-622
The objective of this paper is to clarify the relationships between the quantum D-module and equivariant Floer theory. Equivariant Floer theory was introduced by Givental in his paper ``Homological Geometry'.
He conjectured that the quantum D-module of a symplectic manifold is isomorphic to the equivariant Floer cohomology for the universal cover of the free loop
space. First, motivated by the work of Guest, we formulate the notion of ``abstract quantum D-module' which generalizes the D-module defined by the small quantum cohomology algebra. Second, we define the equivariant Floer cohomology of toric complete
intersections rigorously as a D-module, using Givental's model. This is shown to satisfy the axioms of abstract quantum D-module. By Givental's mirror theorem [Giv3], it follows that equivariant Floer cohomology defined here is isomorphic to the
quantum cohomology D-module. 相似文献