Abstract: The floating point number data processing means is for use in microprocessor systems and finds application in AC motor drive technology. The format used includes a sign bit, a seven bit signed exponent and an eight bit mantissa. The mathematical functions are performed in a gate array using registers which are mapped into a memory of the microprocessor system, the particular mathematical function being dependent upon a particular choice of registers. An unsigned integer comparison of floating point numbers is used to give a correct result.

Abstract: A personal radiation dosemeter comprising a radiation detector means coupled to an electronic measurement circuit arranged in combination therewith to generate signals representative of an amount of radiation detected by the radiation detector. The radiation detector means is arranged to be screened from ambient light and is further provided with a light source optically coupled to the radiation detector and arranged to operate under control of a test control circuit to generate light of a wavelength which may be detected by said radiation detector. This arrangement provides, in combination with said electronic measurement circuit an integrity test for said radiation detector means.

Abstract: A personal radiation dosemeter comprising a radiation detector means coupled to an electronic measurement circuit arranged in combination therewith to generate signals representative of an amount of radiation detected by the radiation detector. The radiation detector means is arranged to be screened from ambient light and is further provided with a light source optically coupled to the radiation detector and arranged to operate under control of a test control circuit to generate light of a wavelength which may be detected by said radiation detector. This arrangement provides, in combination with said electronic measurement circuit an integrity test for said radiation detector means.

Abstract: A process for DRAM cell production includes (1) depositing a layer of a first substance in a trench; (2) depositing a first layer of a second substance in said trench; (3) growing an interfacial layer of oxide between said layer of said first substance and said first layer of said second substance, and between side walls of said trench and said first layer of said second substance; (4) applying an anisotropic etching substance to the surface of said first layer of said second substance, thereby exposing said interfacial layer of oxide; (5) applying a second etching substance to the surface of said first layer of said second substance thereby substantially removing said interfacial layer of oxide; and (6) depositing a second layer of said second substance in said trench. The process reduces the contact resistance of the buried strap and improves the production yield for low temperature performance cells.

Abstract: A traffic light control system comprises a passive infra-red presence detection system for detecting the presence of a target emitting infra-red radiation, which comprises a pyro-electric detector including an array of pyro-electric sensor elements. The pyro-electric detector is arranged to generate a signal representative of movement of the target within a detection zone of the detector. By priding a signal processing unit which operates to analyse pulses present in the signal, the said presence detection system is provided with a means whereby it can not only detect movement of the target within the detection zone but also whether that target has moved into and stopped within the detection zone.

Abstract: An apparatus for reconstituting dried bacteria includes a first reservoir for the storage of reconstituting solution, a pump via which the reservoir is coupled to one of a pair of hollow needles arranged side by side in operative association with an apparatus for raising or lowering the pair so that in use they can be lowered to pierce a closure bung of a container in which bacteria are sealed under vacuum, the one needle being effectively longer than the other of the two hollow needles so that consequent upon lowering of the pair, the one needle passes through the bung before the other effectively shorter of the two needles. The shorter of the two needles is coupled to a second reservoir for the transfer thereto, in use of the apparatus, of reconstitution solution from the first reservoir together with bacteria from the container.

Abstract: A Fourier-transform spectrometer contains a birefringent optical component, removing the need for a Michelson interferometer used in conventional instruments. A suitable birefringent element such as a Wollaston prism, is used to introduce a path difference between two light polarisations. Use of an extended light source so that all areas of the birefringent component are illuminated simultaneously ensures that different positions on the birefringent component correspond to different path differences between the two polarisations. A Fourier-transform of the resulting interferogram at the detector results in the spectral distribution of the input light being obtained. The use of an extended light source permits a Fourier-transform spectrometer with no moving parts to be achieved.

Abstract: A Fourier transform spectrometer for use, among others, for sensing gases or liquids includes two polarizers, a birefringent optical component interposed between the two polarizers and a detector. Light from an extended source is substantially polarized by a first of the two polarizers, split into divergent beams by the birefringent optical component, and again caused to converge by the birefringent optical component so that, after passing through a second of the two polarizers, the light forms an interferogram in a plane behind the birefringent optical component where the detector is situated. The Fourier transform spectrometer is thereby provided with a way of forming an interferogram of the light from the extended source without a lens or a second birefringent optical component. This improves the field of view of the spectrometer and is likely to reduce its cost.

Abstract: Toxicity measuring apparatus comprising a sample reservoir in which an aqueous sample to be tested is stored, a reagent reservoir, a diluent reservoir, a mixing chamber vented via a first valve to atmosphere through an air inlet tube which extends within the chamber towards a lower part thereof, second, third and fourth valves via which the sample, the reagent and the diluent respectively are fed selectively to the mixing chamber in accordance with the open/closed state of the said second, third or fourth valves, a toxicity detector cell fed with a mixture of the sample, the reagent and the diluent from the chamber, within which detector cell aqueous sample measurements are carried out, a linear pump and valve means, via which valve means the mixture is drawn through the detector cell from the chamber by the linear pump, or via which air in an upper part of the chamber is drawn from the chamber by the pump in accordance with the open/closed state of the said valve means, whereby for the purpose of mixing the