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101.
Adjoint‐based and feature‐based grid adaptive strategies are compared for their robustness and effectiveness in improving the accuracy of functional outputs such as lift and drag coefficients. The output‐based adjoint approach strives to improve the adjoint error estimates that relate the local residual errors to the global error in an output function via adjoint variables as weight functions. A conservative adaptive indicator that takes into account the residual errors in both the primal (flow) and dual (adjoint) solutions is implemented for the adjoint approach. The physics‐based feature approach strives to identify and resolve significant features of the flow to improve functional accuracy. Adaptive indicators that represent expansions and compressions in the flow direction and gradients normal to the flow direction are implemented for the feature approach. The adaptive approaches are compared for functional outputs of three‐dimensional arbitrary Mach number flow simulations on mixed‐element unstructured meshes. Grid adaptation is performed with h‐refinement and results are presented for inviscid, laminar and turbulent flows. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
102.
The effect of pulsed electric fields on biological cells:experiments and applications 总被引:1,自引:0,他引:1
Schoenbach K.H. Peterkin F.E. Alden R.W. III Beebe S.J. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(2):284-292
The effect of pulsed electric fields with amplitudes in the range of 100 V/cm-100 kV/cm on bacteria and aquatic nuisance species has been explored. The pulse duration was so short that heating of the biological matter could be neglected. The electrical energy required for lysing of bacteria, or stunning of aquatic species, decreases when the pulse duration is reduced. For lysing of Eschericia coli, this tendency has been proven to hold for pulsewidths as short as 60 ns. For macroorganisms, however, it was found that for pulsewidths of less than 5 μs, the tendency is reversed: the energy required to affect the macroorganisms increases again. This minimum in energy, or maximum in efficiency, respectively, can be understood by taking the time required for electrical charging of the cell membrane into account. Applications of the pulsed electric field technique (PEFT) are in biofouling prevention, debacterialization of liquids, and in the field of medicine. A series of field tests on biofouling prevention in a cooling system with untreated water as coolant has demonstrated the economic feasibility of the electro-technology 相似文献
103.
A. Alessandrello C. Arnaboldi F. T. Avignone III J. Beeman M. Barucci M. Balata C. Brofferio C. Bucci S. Cebrian R. J. Creswick S. Capelli L. Carbone O. Cremonesi A. de Ward E. Fiorini H. A. Farach G. Frossati A. Giuliani D. Giugni E. E. Haller I. G. Irastorza R. J. McDonald A. Morales E. B. Norman P. Negri A. Nucciotti M. Pedretti C. Pobes V. Palmieri M. Pavan G. Pessina S. Pirro E. Previtali C. Rosenfeld A. R. Smith M. Sisti G. Ventura M. Vanzini L. Zanotti 《Physics of Atomic Nuclei》2003,66(3):452-457
CUORE is a proposed tightly packed array of 1000 TeO2 bolometers, each being a cube 5 cm on a side with a mass of 750 g. The array consists of 25 vertical towers, arranged in a square of 5 towers by 5 towers, each containing ten layers of four crystals. The design of the detector is optimized for ultralow-background searches for neutrinoless double beta decay of 130Te (33.8% abundance), cold dark matter, solar axions, and rare nuclear decays. A preliminary experiment involving 20 crystals of various sizes (MIBETA) has been completed, and a single CUORE tower is being constructed as a smaller scale experiment called CUORICINO. The expected performance and sensitivity, based on Monte Carlo simulations and extrapolations of present results, are reported. 相似文献
104.
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106.
Absence of Charge-Resonance-Enhanced Ionization in Attosecond Pulse Photoionization: Numerical Result on One-Dimensional H2^+ 下载免费PDF全文
We present a numerical result of photoionization rate for the one-dimensional molecular hydrogen ion model exposed to intense light of 1 × 10^16-2×10^16 W/cm^2, 55-as pulse duration, and 800nm wavelength. In contrast to the previous calculation result of charge-resonance-enhanced ionization for lower intensity and much longer pulse, our result exhibits an ionization saturation. The numerical results are interpreted in the field-dressed potential picture as over-the-barrier liberation of electrons. This extremely short pulsewidth and relatively high field phenomenon requests experimental demonstration. 相似文献
107.
108.
B. Durig F. Zhang S.R. McNeill Y.J. Chao W.H. Peters III 《Optics and Lasers in Engineering》1991,14(3)
In this paper, the results from two experimental methodologies, photoelasticity aided by digital image processing and precision digital image correlation, are presented for a mixed mode fracture problem. The mixed mode fracture problem was a three-point-bend edge-crack specimen which was loaded at various off-crack-line locations between the crack line and the specimen support line. The estimations of KI and KII from both methodologies indicate that the crack tip stress field is strongly intensified by KI but not KII. 相似文献
109.
Oscar E. Lanford III 《Communications in Mathematical Physics》1984,96(4):521-538
We use the Leray-Schauder Fixed Point Theorem to prove the existence of an analytic fixed point for the period doubling accumulation renormalization operator. Our argument does not, however, show that the linearization of the renormalization operator at this fixed point is hyperbolic. 相似文献
110.