Abstract:
A compaction compensation system comprising a mechanism for automatically height adjusting the height adjustable mounting (30) so as to height adjust the sensor relative to the screed by a compaction compensating factor. It is used in a paving machine (1) for laying compactable paving material, the paving machine comprising: (a) a height adjustable screed (5) for laying a layer of compactable paving material onto a surface; (b) a sensor (15,17) for sensing the height of the screed relative to a reference level, the sensor being attached to the screed by a height adjustable mounting; (c) a screed height control system for automatically adjusting the height of the screed in response to different heights sensed by the sensor due to contours of the surface, so as to adjust the screed to lay a layer of varying thickness.
Abstract:
The present application provides a method of calculating DC-DC converter power losses without the requirement for a measurement of input current. The application also describes the use of such a calculation to determine the optimum point for switchover between a single phase mode or dual phase mode in a two phase DC-DC power supply.
Abstract:
A fibre-optic module incorporating a semiconductor optical amplifier is compatible with a standard specification for a fibre-optic transceiver module, which is typically pluggable. The module comprises optical connectors capable of connection to first and second optical fibres and being in accordance with said standard specification and the input optical signal received from the first optical fibre is amplified by the semiconductor optical amplifier and supplied to the second optical connector for transmission along the second optical fibre. The module further comprises an electrical parallel connector having a physical configuration in accordance with said standard specification and a control circuit which receives control signals from the electrical parallel connector and to control the operation of the optical amplifier. Thus the module maybe connected to a standard electrical backplane alongside fibre-optic transceiver modules to augment the optical performance of the transceiver modules.
Abstract:
Apparatus for drying a gas comprises an elongate housing having an inlet port and an outlet port for the gas. The housing comprises at least two axially separable parts which can be separated to allow access to the interior of the housing. A cartridge contains an adsorbent material through which gas can flow axially from an inlet end which is in fluid communication with the inlet port to the housing towards an outlet end which is in fluid communication with the outlet port from the housing. The cartridge has a plurality of flexible vanes at the inlet end which, when the cartridge is located within the housing, are twisted so that gas flowing over the vanes has a circumferential flow imparted to it around the axis of the cartridge.
Abstract:
A polarisation control device having a polarisation converter (22) in a first section (B)of an optical waveguide (15) with a gradually varying asymmetrical cross - sectional (transverse) profile and an active phase shifter (38) in a second section (C) of the optical waveguide whose birefringence is adjustable by a relative phase controller. The polarisation converter (22) converts an orthogonal fundamental mode (TE or TM) into a hybridised signal present in the active phase shifter (38). The first and second sections (B, C) of waveguide are joined to one another to form a single continuous waveguide (15), which can significantly reduce interfacial reflections.
Abstract:
The Application is directed at arrangements in which switch mode power converters share a common load. More particularly, the application provides a masterless arrangement in which no single converter controls the operation of the other converters. This is achieved by an arrangement in which each converter attempts to share its current measurement with other converters through an arbitration scheme employed on a data line, with the winning converter providing a defacto current measurement, for example a maximum or minimum, to the overall arrangement.
Abstract:
A method and a device serve to locally impregnate a piece of wood (6) with a gaseous or liquid wood impregnation agent, which is injected under pressure by means of an injection apparatus (70) into a hole (7), which is drilled in the wood and closed with a valve (44) defining a cavity (10). To obtain the greatest possible propagation of the impregnation agent in the wood the air of the cavity (10) is first removed either by flushing the cavity with impregnation agent or directly evacuating the cavity of air. The device comprises an elastomeric valve (44) having at least one internal valve channel (42, 63) which is clamped tightly together along a portion in the longitudinal direction when the valve is pressed into the drilled hole, as well as an injection apparatus having a needle associated with each valve channel to drive into the respective valve channel upon injection and thereby connect the injection apparatus with the hole. The valve channels are closed with pins after the injection, which are provided on a disc that changes its colour after a predetermined period of time of e.g. 3 years to indicate that impregnation should be repeated.
Abstract:
An optical amplifier comprising a signal semiconductor optical amplifier (SOA) (1) and a control SOA (2) in an optical circuit comprising a signal path (4) passing through the signal SOA (1) and a laser cavity containing both the signal SOA (1) and the control SOA (2). The control SOA (2) may be arranged outside the laser cavity so that it does not amplify a signal in the signal path (4). Alternatively, the control SOA (2) is arranged in the signal path (4), but has insignificant gain in the predetermined signal band (3) so that it does not amplify a signal passing along the signal path (4). The laser cavity clamps the total gain of the signal SOA (1) and the control SOA (2). In use, the bias current supplied to the control SOA (2) is varied to control the clamped-gain of the signal SOA (1). Therefore the gain of a signal passing along the signal path (4) is clamped to a level which may be varied by control of the control SOA (2). In an alternative type of embodiment, a similar type of control is achieved in a structure integrated in a single semiconductor chip. In particular a waveguide (56) extends along a signal active layer (52) and a laser cavity arranged perpendicularly to the layered structure of the semiconductor chip contains both the signal active layer (52) and a control active layer (59) which corresponds to the control SOA (2).
Abstract:
The present invention relates to a portable clothes dryer. In particular an external dryer cover which is impervious to air. The impervious cover encompasses an inflatable shaped bladder which is not impervious to air. Heated air can permeate the internal bladder and any garments placed on the inner bladder. With the cover in place air is not immediately lost to the atmosphere, instead the heated air temporarily retained by the external cover. The advantage of the invention is hot air is recycled and not wasted. It reduces heat loss, improves drying times and energy efficiency. The extremal cover has one or more venting apertures.
Abstract:
The present application provides a tunable compensator providing a control signal to control a switch in a power supply. A measurement is taken of the level of activity of the control signal. This measurement is used to introduce a bias into a tuner tuning the compensator when the amount of activity in the control signal drops.