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81.
The application of reflex optoelectronic switching matrices (ROSM) to signal processing in the gigahertz region is analyzed. Various signal processing functions such as delay generation, loop filtering, word generation/detection, integration, and digital to analog conversion are identified and their respective realizations in a ROSM are presented. It is found that for dedicated signal processing functions, simpler submatrices instead of full matrices can be employed with significant reduction in complexity and cost. The performance of ROSM's using currently commercially available components confirms the feasibility of gigahertz signal processing with ROSM's. 相似文献
82.
V. B. Larin 《Ukrainian Mathematical Journal》1989,41(5):532-538
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 41, No. 5, pp. 615–621, May, 1989. 相似文献
83.
An optimization design model for surface termination of off-state semiconductor devices under reverse-bias conditions is presented. The multivariable design model is used to optimize the surface profile shapes for nonplanar devices and the doping profiles of material regions along the surface for planar devices. The effectiveness of the design model in reducing the peak surface electric field to below 50% of the bulk value is demonstrated for two examples of each type of device 相似文献
84.
Phase synchronization in a system of three virtual-cathode microwave oscillators (vircators) simulated by coupled van der Pol oscillators is studied. The phasing dynamics of the vircators is visualized with the phase portraits of the system in the triangular coordinates. Different phasing conditions are found. 相似文献
85.
86.
In this paper, we study the consistency of a variant of fractionalstep Runge–Kutta methods. These methods are designed tointegrate efficiently semi-linear multidimensional parabolicproblems by means of linearly implicit time integration processes.Such time discretization procedures are also related to a splittingof the space differential operator (or the spatial discretizationof it) as a sum of simpler linear differentialoperators and a nonlinear term. 相似文献
87.
88.
We study the nonlinear propagation of light in optical fibers in the strong nonlinearity limit. In this limit, the transverse guiding properties are altered and cannot be decoupled from the longitudinal part of the wave equation. We consider a refractive index profile with no bound modes at low intensities and show that stable self-guiding occurs at a critical intensity. This critical intensity is a property of the guide and can be made much lower than the threshold for unstable self-focusing. We consider a particular design for which self-guiding occurs at three orders of magnitude lower than the self-focusing threshold. 相似文献
89.
I A Bukaeva L A Iakovleva B A Lapin L V Indzhiia E M Kobe 《Eksperimental?nai?a onkologii?a》1987,9(4):26-30
The results of morphological study of B- and T-cellular immunoblast baboon lymphomas are presented. Differences are found both in the structure of tumour cells and in the histostructure of tumours as a whole. The tumor cells of B-immunoblastic lymphomas expressed mainly IgM. The tumour cells of certain T-immunoblastic lymphomas being investigated by means of monoclonal OKT4 antibodies had a surface phenotype peculiar to T-helper cells. 相似文献
90.
Koch B. Hidayat A. Hongbin Zhang Mirvoda V. Lichtinger M. Sandel D. Noe R. 《Photonics Technology Letters, IEEE》2008,20(12):961-963
We demonstrate endless polarization stabilization with a control speed of up to 9 krad/s, over random Poincare sphere trajectories. These are in total >35 Mrad long, are composed in particular of difficult-to-track circles with all radii and orientations, and thereby include all possible worst cases. The maximum polarization mismatch and relative intensity errors are 0.13 rad and 0.43%, respectively. The controller runs on a field-programmable gate array and uses a commercial multistage LiNbO3 polarization transformer as the control device. 相似文献