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961.
962.
963.
The uniaxial bianisotropic medium is a generalisation of the bi-isotropic and chiral media which recently have been subject to intensive research. Such a medium results, for example, when microscopic helices with parallel axes are positioned in a host dielectric in random locations. Plane wave propagation in such a medium is studied and a simple solution for the dispersion equation is found. Numerical examples for the wave number surfaces of the medium are given.<> 相似文献
964.
Effects of rapid thermal annealing (RTA) on sub-100 nm p+ -n Si junctions fabricated using 10 kV FIB Ga+ implantation at doses ranging from 1013 to 1015 cm -2 are reported. Annealing temperature and time were varied from 550 to 700°C and 30 to 120 s. It was observed that a maximum in the active carrier concentration is achieved at the critical annealing temperature of 600°C. Temperatures above and below the critical temperature were followed by a decrease in the active concentration, leading to a `reverse' annealing effect 相似文献
965.
966.
Nonlinear boundary element analysis provides a more accurate and detailing tool for the design of switched reluctance machines than conventional equivalent-circuit methods. Design optimization through more detailed analysis and simulation can reduce development and prototyping costs and time to market. Firstly, magnetic field modeling of an industrial switched reluctance machine by the boundary element method is reported in this paper. Secondly, performance prediction and dynamic simulation of motor and control design are presented. Thirdly, magnetic forces that cause noise and vibration are studied, to include the effects of motor and control design variations on noise in the design process. Testing of such a motor in the NEMA 215-Frame size is carried out to verify the accuracy of modeling and simulation 相似文献
967.
M. L. Rojas-Cervantes A. J. Lopez-Peinado J. De D. Lopez-Gonzalez F. CarrascO-Marin 《Journal of Materials Science》1996,31(2):437-444
Some zirconia-supported vanadium oxides have been prepared by sol-gel method and characterized by different techniques. The vanadium content exerts an effect on the area and pore-size of precursors and samples calcined. The presence of vanadium also affects the decomposition of precursors into ZrO2 and to its phase transformation, as well as the formation of fibres, as shown by SEM-EDX. XPS analyses show the presence of two species of vanadium at the surface, V5– and V4+, the percentage of each one depending on the load of vanadium in the catalyst. 相似文献
968.
Is the loop, which provides customers with access to the switchednetwork, a service in its own right, or is it purely an inputinto the production of the final service, which is usage ofthe switched network? Agreeing with Kahn and Taylor that thequestion of whether the loop is an economic good is irrelevantto the pricing issue, this paper goes on to claim that pricingat marginal cost is not an appropriate welfare maximizationrule due to network externalities that make the private benefitof access less than the social benefit. Socially efficient pricingis likely to involve pricing below the marginal cost of accessto some consumers and above the marginal cost of access to others.One implication is that a contribution to the local loop fromInterexchange Carriers (IXCs) or IXC customers may be optimal. 相似文献
969.
Ives J.T. Gesteland R.F. Stockham T.G. Jr. 《IEEE transactions on bio-medical engineering》1994,41(6):509-519
An automated reader for electrophoresis based DNA sequencing methods is described that provides fast and accurate sequence determination. Digitized sequencing lanes are processed with homomorphic blind deconvolution in preparation for peak detection, interlane alignment, peak refinement and base calling. Initial reads from direct blot sequencing films have error rates of about 1% at the rate of 5 nucleotides/s. Typical read lengths are 500-600 nucleotides. The described reader is a significant improvement over existing readers and could be an essential component in the sequencing efforts of the Human Genome Project 相似文献
970.
A new type of fiber laser modelocking is examined where a phase modulator is driven asynchronously with respect to a harmonic of the roundtrip cavity frequency. An asynchronous drive is able to produce high repetition rate (>1 GHz) soliton pulses that are shorter than the classic, active modelocking pulse width limit. It is shown that with a proper choice of fiber parameters, noise cleanup and soliton pulse shaping can be obtained using filtering and asynchronous phase modulation. Limits of asynchronous detuning are derived and a comparison with the parameters ranges for synchronous phase modulation is also presented 相似文献