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991.
A near-field preconditioner and its performance in conjunction with the BiCGstab(ell) solver 总被引:6,自引:0,他引:6
This paper describes a simple physically-motivated "near-field" preconditioning scheme that is effective in accelerating convergence of surface, volume, and combined surface/volume integral equations for a broad variety of electromagnetic scattering problems. It can be easily implemented numerically in method of moment (MoM) solvers (both conventional and those employing matrix-compression techniques), irrespective of the analytical form of the integral-equation kernel. It has low memory and CPU requirements, both of which scale linearly with the number of unknowns, and is easily amenable to efficient parallelization. We demonstrate the preconditioner's performance (in conjunction with the BiCGstab(ell) iterative solver) on two representative geometries, and observe a significant reduction in the number of iterations required for convergence. 相似文献
992.
993.
Electrolytic hydrogen saturation of polycrystalline aluminum leads to a significant (up to about 30%) decrease in the shear moduli G of samples. This change in G is accompanied neither by the loss of plasticity (no hydrogen-induced brittleness) nor by a change in the electric resistance (in contrast to that observed during the hydrogenation of typical hydride-forming metals and alloys, including those in the amorphous state). 相似文献
994.
An integrated process based on simultaneous solid-liquid extraction and liquid membrane separation is proposed for recovery and isolation of valuable species from botanicals. This integration provides complete exhausting of the solid material even in the case of very low solubility of the specified solute in the extracting solvent. Selectivity of the liquid membrane ensures a preferential transport of the desired solute from the native extract into the strip solution, while the other co-extracted species remain predominantly in the native extract. 相似文献
995.
Yu-Li Hsueh Jaedon Kim Ching-Fong Su Rabbat R. Hamada T. Tian C. Kazovsky L.G. 《Lightwave Technology, Journal of》2006,24(1):44-53
A sublambda traffic-grooming scheme on wavelength-division-multiplexed (WDM) rings, which is called optical burst transport (OBT), is proposed. The network protocol and architecture allow increased flexibility to tailor the transport network behavior for efficient delivery of bursty data traffic. Using different network parameters, its performance is analyzed via simulation, and the implementation issues including the media-access-control (MAC) protocol, tunable-filter controller, and burst-mode receiver are addressed. Finally, the feasibility of the OBT with an experimental testbed built by the authors is demonstrated and a streaming-video application is used to present its overall functionality. 相似文献
996.
997.
A novel soft decision-based median subtraction filter is presented for clutter suppression and infrared (IR) point targets enhancement. The decision is made based on a jump Markov model and its state and parameter estimation using a particle filter. The scheme is compared with other conventional clutter background removal techniques and good results are obtained. 相似文献
998.
James L. Gardner 《Color research and application》2006,31(5):374-380
The spectral bandwidth formulae of Stearns and Stearns are generalized for an arbitrary slit function. Correction coefficients are derived in terms of moments of the slit function. Application to model LED spectra measured with a compact, fiber‐coupled spectrometer having bandwidth of order 12 nm, and a nonlinear wavelength scale shows that accurate LED color measurements may be obtained with such an instrument. Fitting of the relatively broad slit function to line spectra for accurate wavelength calibration is also described. Such fitting, coupled consistently with the bandpass correction, improves the accuracy color measurements with a broad‐response spectrometer. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 374–380, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20242 相似文献
999.
A general variance predictor for Cavalieri slices 总被引:1,自引:0,他引:1
L. M. CRUZ-ORIVE 《Journal of microscopy》2006,222(3):158-165
A general variance predictor is presented for a Cavalieri design with slices of an arbitrary thickness t ≥ 0. So far, prediction formulae have been available either for measurement functions with smoothness constant q = 0, 1, … , and t ≥ 0, or for fractional q ∈ [0, 1] with t = 0. Because the possibility of using a fractional q adds flexibility to the variance prediction, we have extended the latter for any q ∈ [0, 1] and t ≥ 0. Empirical checks with previously published human brain data suggest an improved performance of the new prediction formula with respect to the hitherto available ones. 相似文献
1000.
This paper shows how the theory of nonlinear adaptive observers can be effectively used in the design of internal models for nonlinear output regulation. The theory substantially enhances the existing results in the context of adaptive output regulation, by allowing for not necessarily stable zero dynamics of the controlled plant and by weakening the standard assumption of having the steady-state control input generated by a linear system. 相似文献