Ashley Cullen

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SUMMARY It is shown that a surface wave will be generated by a horizontal.slot situated above a corrugated or dielectric-coated guiding surface. A physical interpretation of the analysis is suggested which explains the mechanism of launching in terms of a resonance phenomenon allied to that which arises when a piston attenuator is terminated by a reactance(More)
Daily quality assurance procedures are an essential part of radiotherapy medical physics. Devices such as the Sun Nuclear, DQA3 are effective tools for analysis of daily dosimetry including flatness, symmetry, energy, field size and central axis radiation dose measurement. The DQA3 can be used on the treatment couch of the linear accelerator or on a(More)
SUMMARY The paper is an attempt to present, in the simplest possible terms, a unified picture of the theory of various forms of surface wave and a clear physical interpretation of their behaviour. The Zenneck wave, the radial cylindrical surface wave and the Sommerfeld-Goubau or axial cylindrical surface wave are each discussed and shown to represent(More)
Two term infants suffering severe asphyxial events were found to have diffusely high attenuation of the cortical gyri on CT scanning within 12 days. The findings are consistent with haemorrhagic necrosis or microcalcification. This feature has rarely been described in the literature. The evolution of the CT appearance, the possible neuropathological(More)
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