background: the heterogeneous composition of the human body presents numerous tissue types and cavities with widely differing radiologic properties. the aim of the present work was to develop a low cost homogeneous and heterogeneous phantom and the absorbed dose were measured by ionization chamber for different radiotherapy treatment techniques and compared with treatment planning system absorb...

The transreal numbers are a total number system in which every arithmetical operation is well defined everywhere. This has many benefits over the real numbers as a basis for computation and, possibly, for physical theories. We define the topology of the transreal numbers and show that it gives a more coherent interpretation of two’s complement arithmetic than the conventional integer model. Tra...

1. Pulling forces of Chrysolina polita (L.) on glass, perspex and cloth have been recorded and are plotted against body weight. The additional weight of eggs in many of the females is probably the main reason that, in females, pulling forces do. not increase significantly with body weight, whereas those of males do. 2. Pulling forces on glass and perspex are significantly correlated but, in gen...

We have designed, and are in the process of building, a visualisation device, the Cub-e. The Cub-e consists of six TFT screens, arranged in a perspex cube, with a StrongARM processor and batteries inside. It is a multipurpose device with applications including teleconferencing, interaction with virtual worlds, and games.

We study squeeze flow of two different fluids (castor oil and ethylene glycol) between a pair of glass plates and a pair of perspex plates, under an applied load. The film thickness is found to vary with time as a power-law, where the exponent increases with load. After a certain time interval the area of fluid-solid contact saturates to a constant value. This saturation area, increases with lo...

The tube in flow rigs used for testing Doppler ultrasound instruments can attenuate and distort the beam and sample volume by refraction, reflection, absorption and mode conversion. The attenuation and degree of distortion has been measured by using a moving string test object and candidate tubes have been compared. Tubes of rubber, TFE-Teflon, Perspex, heatshrink and C-Flex have been tested le...

A low cost perspex buffer rod design for the measurement of specific gravity during the processing of industrial food batters is reported. Operation was conducted in pulsed mode using a 2.25MHz, 15mm diameter transducer and the intensity and an analytic calibration curve relating buffer rod output to specific gravity is obtained. The probe design may have application to other similar mixtures o...