摘要:
A radio telephone system has a plurality of base stations (3, 4) and a plurality of mobile radios. The position of the mobile radios are determined by combining information at the base stations (3, 4) with information from additional position indicators, such as beacons (16a, 16b, 16c) placed at intervals alongside a railway track (8). This enhanced information on the positions of the mobile radios enables channels to be reused on mobile radios with less physical separation than hitherto, thereby improving the efficiency of channel allocation.
摘要:
A power transmission line, apparatus for and method of control thereof are provided to enable loads connected between the live and neutral conductors to be reconnected to a power supply following the occurrence of a short circuit upon the line, without the need to first repair the short circuited section of the line. The power line comprises a plurality of locations (8), each comprising a Signalling Power Management System (SPMS) unit (10) and a location transformer (12). The SPMS unit (10) comprises an impedance (18), which impedance and the location transformer (12) form a potential divider across the power supply. By comparing the voltages across the impedance (18) and the location transformer (12), a controller (28) determines whether there is a short circuit on the section of the power line downstream from the location transformer (12) as far as the next SPMS unit. Only if there is no short circuit upon this section does the controller (28) close a relay (26) in parallel with the impedance (18) such that all of the power supply voltage is dropped across the location transformer (12).
摘要:
A confocal scanning optical microscope system wherein a dispersive optical device such as a prism (28) separates an image from a restricted area of a specimen into a spread of images of differing wavelengths. Different parts of the spread of images are focussed at respective beam-limiting apertures (34, 36) which are conjugate with one another, and the spectrally differing beams passing through the beam-limiting apertures pass to respective detectors (35, 37).
摘要:
The invention provides a display device (99) comprising a generally flat body member (1) that has a visually transparent viewing section. On the rear surface of the body member (1) are two functionally separate elements (2, 3). The first element (2) provides support for a photograph (4) to be displayed through the visually transparent section of the body member (1). The second element (3) attaches to any suitable surface to support the display device, and any photograph (4) the first element (2) may be supporting.
摘要:
A method and machine for preparing and dispensing documents relating to financial transactions. The machine contains an ink jet printer for printing the documents and a bar code reader mounted for movement with the print head of the printer for reading bar codes on each document before or during printing. The machine includes a control unit having personal computer architecture including a CPU, memories and input/output devices. One of the devices is a modem allowing communication with a remote supervisory location. Operation of the machine is controlled from the remote supervisory location, which provides periodic authorization to continue to prepare and dispense documents in response to transaction reports transmitted from the machine to the remote supervisory location. A wide variety of documents can be prepared and dispensed under control of software in the control unit.
摘要:
An autoclave type sterilization device which includes an autoclave sterilization chamber with an electrical heating arrangement mounted thereon. This electrical heating arrangement employs one or more positive temperature coefficient (PTC) thermistors as heating elements. These heating elements are in direct thermal and electrical contact on opposing sides, which are coated with a conductive metal such as aluminum, with electrodes to supply electrical current. These electrodes are, in turn, in direct thermal contact on their outward-facing sides with respect to the heating elements with plates which are formed of a thermally conductive and electrically insulating ceramic material such as AL 2 O 3 , and the plates are in direct thermal contact on their outward-facing sides with respect to the heating elements with heat radiation units which include heat transfer portions which are fabricated to engage and are in direct thermal contact with a portion of the wall of the autoclave chamber. The heating elements are positioned by an electrically and thermally insulating frame made of heat-resistant material which serves, together with the heat radiation units, to fully enclose the heating elements. The heat radiation units further are in thermal and mechanical contact with each other which, together with the abovementioned enclosure of the heating elements, protects them from thermal gradients due to unbalanced heat transfer or exposure to air or gas flow and hence, from the known "pinch effect."
摘要:
A filter assembly for filtering pond or aquarium water comprises a container (1,2) with an inlet chamber (15) having an upstream region (36) and a downstream outlet (13) leading to an outlet chamber (22). A filter (16) is positioned in the inlet chamber (15) between the upstream region (36) and the outlet (13). In use, progressive clogging of the filter causes the water pressure in the upstream region (36) to rise until it reaches a predetermined threshold when a normally-closed relief valve (28, 29) opens to allow water to pass from the upstream region (36) to the outlet chamber (22) without passing through the filter (16). The valve has a coloured valve stem (28) providing a visual indication that the valve is open and that the filter is blocked and requires cleaning. In one embodiment, the outlet chamber (22) contains a source (19) of ultra-violet radiation to which the flow of water is exposed, regardless of whether the valve (28,29) is in the open or closed condition.
摘要:
An aircraft seat has a frame assembly onto which is attached a shaped front cover (7) by means of clips (9, 12), each having a socket component and a plug component. The plug and socket components are repeatedly engageable and disengageable, enabling the front cover (7) to be repeatedly removed from and refitted to the frame assembly, for example for cleaning of the front cover (7). The clips (, 12) ensure accurate and precise fitting and location of the seat cover (7) with respect to the frame assembly.