Cuthbert M. Allen

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current distribution is windowed, and the level of the edge singu-larity is reduced by this process, the computed RCS shows a much better agreement over the entire region. It should be noted that the values of the RCS at grazing angles to the plate are weak, and are on the order of Ϫ25 dB, as compared to the backscattering RCS. Hence, an accurate prediction(More)
BACKGROUND The Call-Fleming syndrome (CFS) comprises acute severe recurrent (thunderclap) headaches, occasional transient or fluctuating neurological abnormalities and reversible segmental cerebral vasoconstriction. It is a benign condition with an excellent prognosis, yet because it is often clinically and radiologically similar to a number of commonly(More)
—A dual tapered meander slot antenna (TMSA) is designed for use as an element in a phased array antenna system for RF and microwave sensors and radar applications. The novel design of dual TMSA element, excited by a coplanar waveguide (CPW) feed, provides a wide band and high efficiency characteristics with 50 input impedance at 10 GHz operating frequency.
Two antenna designs were achieved for dual and wide band operation in wireless systems. One design was realized using a tapered meander slot with a microstrip feed to give dual band operation at 1.8 and 2.4 GHz. In this design both operating frequencies are controlled mainly by the horizontal slot width of the meander and the distance of the microstrip line(More)
ACKNOWLEDGMENTS The authors would like to acknowledge H. Lafontaine and S. Kovacic for their help with models and technology. et réalisation d'un filtre actif de type RC utilisant un amplificateur de gain fini en technologie MMIC, Ph. Very small MMIC variable frequency and Q factor active bandpass filters using novel positive and negative feedback design(More)
A method for making clinico-anatomical correlations by computer superimposition of brain maps derived from CT scan images, described in a companion paper, was tested in 19 patients with an uncomplicated left hemiparesis due to acute stroke. Eight patients with an isolated left hemiparesis had small lesions in the most rostral part of the right internal(More)
A method used to produce composite drawings of superimposed areas of brain infarction is described. The method uses a microcomputer interfaced to a digitising pad and linear plotter. Areas of brain damage are drawn on standardised maps, digitised, manipulated in computer memory, and summated using computer graphics facilities. The composites show the(More)
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