Abstract: The specification discloses a method and apparatus for irradiating foodstuffs. The method comprises the step of exposing a foodstuff to be irradiated to x-rays having energies selected exclusively from the range of below approximately 250 KeV, for a period of time and at at least a first intensity sufficient to provide a desired dose of radiation to the foodstuff. The inventive apparatus comprises, in a first embodiment, a conduit adapted for the movement therethrough of a foodstuff to be irradiated, the conduit having a passageway defined between inlet and outlet ends thereof; means for moving the product to be irradiated through the conduit at at least a first velocity; and at least one x-ray tube disposed within the conduit passageway between the inlet and outlet ends in the path of travel of the foodstuff to be irradiated, the at least one x-ray tube being selectively capable of generating x-rays having energies exclusively in the range of below approximately 250 KeV.

Abstract: An electrically powered air freight container (1) includes an insulated housing (2) and a refrigeration unit (3). The refrigeration unit (3) is powered by a voltage and frequency converter which receives electrical power either aircraft generated from either an airport ground source of power or an aircraft source of power which is appropriate to power the refrigeration unit (3) The refrigeration unit (3) is powered by a voltage and frequency converter which receives either airport power at 240 volt or 115 volt or aircraft power at 115 volt (400 Hz) and converts the supply to a voltage and frequency appropriate to power the refrigeration unit (3). The air contained in the housing is free to expand in the event of rapid depressurisation by the provision of blow out covers (19) which close ducts (15).

Abstract: The invention relates to an apparatus for performing electronic shearography on a test object, especially a tire or retread tire. The apparatus uses a laser light source to illuminate the test object. An optical element through which electromagnetic radiation is reflected from the test object is transmitted and forms a random interference image. The random interference image can be electronically processed to provide a video animation of the effects of stress on the test object. An archive memory can be provided for retaining the animation data which can be compressed such that it includes only preselected individual shearogram images from the set of sequential shearogram images and less than all of the image data associated therewith. An air handling system can be provided for changing the ambient pressure in a pressure chamber within which the test object is supportable. The air handling system can include a humidity reducing mechanism.

Abstract: A method and apparatus for an event detector using an array of passive infrared detector elements, which uses interchangeable spectral filters and lenses to permit detection of a range of event types, which normally each require individual detectors with specific spectral/optical designs.

Abstract: In order to determine the position of an object within an area viewed by a single detector of an array, signals from detectors adjacent to the single detector are compared with each other and/or the single detector. The method can be extended to larger objects to ascertain the locations of edges.

Abstract: A surveillance system using an array of detectors onto which energy from the scene under surveillance is focused can indicate the direction of an event that has been recognized. The invention uses two or more arrays to locate events in three dimensions, and to define regions within the three dimensional space being surveyed. The events are located by detecting which elements from the respective arrays are stimulated by the occurrence of an event, and determining the location of the event to be at the intersection of the fields of view of the stimulated elements.

Abstract: An image of a scene is focused onto a two dimensional array of passive infrared sensing elements mounted on and connected to an integrated circuit, and used to detect the location of events within the scene; for example, movement, change in temperature, or the emission of a gas. In this invention knowledge of the location of the event is derived from the detection of signals from one or more elements of the array, and is used to control the operation of a mechanism such that a portion of the scene including the event location is imaged onto a video imaging device operating in the visible or near infrared. Such mechanisms include a zoom lens or mirror arrangement and mechanical scanning in elevation and/or azimuth. Examples of suitable imaging devices for use with the thermal detector array include CCD camera chips and other electrically scanned silicon photovoltaic arrays. The CCD array might for example be used in a CCD camera, which is used to identify an intruder, or to read the number plate of a car.

Abstract: An optical detection system for forming an image of a field of view in an object plane onto an image plane in which the electromagnetic radiation image is transmitted to a detector array at the image plane via an optical distorting element such as a reflector 11, so as to impose a non linear relationship between areas in the image and object planes.

Abstract: A method and apparatus for an event detector using an array of passive infrared detector elements, which uses interchangeable spectral filters and lenses to permit detection of a range of event types, which normally each require individual detectors with specific spectral/optical designs.

Abstract: The invention relates to an apparatus for performing electronic shearography on a test object, especially a tire or retread tire. The apparatus uses a laser light source to illuminate the test object. An optical element through which electromagnetic radiation is reflected from the test object is transmitted and forms a random interference image. The random interference image can be electronically processed to provide a video animation of the effects of stress on the test object.

Abstract: An operational amplifier (34) has its inverting input connected to a electrochemical gas sensor (38) for amplifying the current produced thereby in response to presence of a predetermined gas. In order to determine whether a sensor (38) is indeed present and that a sensor present is serviceable, a transient is applied to the non-inverting input of the operation amplifier (34). The presence or absence of the sensor (38) alters the transfer function of the operational amplifier (34) in respect of the test signal. If a serviceable sensor (38) is present, the gain of the operational amplifier (34) is high for the transient resulting at square pulse output. However, if a serviceable sensor (38) is not present, the gain of the operational amplifier (34) is relatively low and the transient retains its original form. Consequently the presence of a serviceable sensor (38) can be determined from the output of the operational amplifier (34) in response to the transient test signal.

Abstract: An operational amplifier (34) has its inverting input connected to a electrochemical gas sensor (38) for amplifying the current produced thereby in response to presence of a predetermined gas. In order to determine whether a sensor (38) is indeed present and that a sensor present is serviceable, a transient is applied to the non-inverting input of the operation amplifier (34). The presence or absence of the sensor (38) alters the transfer function of the operational amplifier (34) in respect of the test signal. If a serviceable sensor (38) is present, the gain of the operational amplifier (34) is high for the transient resulting at square pulse output. However, if a serviceable sensor (38) is not present, the gain of the operational amplifier (34) is relatively low and the transient retains its original form. Consequently the presence of a serviceable sensor (38) can be determined from the output of the operational amplifier (34) in response to the transient test signal.

Abstract: The presence of a serviceable electrochemical gas sensor (1) in gas detecting apparatus is determined on the basis of the noise in the output of a sensor amplifier. A microcomputer (22) calculates mean, rms or variance values for the noise in the output of the amplifier (20) for successive periods. Each of these values is compared with the threshold and if it falls below the threshold, counter is incremented. When the counter reaches a target value, it is determined fault condition as arisen and an alarm (23) is operated.

Abstract: A door for a cupboard and more especially a corner cupboard comprising a planar closure member formed in two sections of different width with one hingedly connected to the other, a first of said section being adapted for hinged mounted to an aperture in which in use the closure member is to be located. In order to control throughout the opening and closing operations of the door the outer or second section an arm is provided. The arm is pivotally coupled adjacent to the free edge of the second section of the door this edge being opposite to the edge of second section which is hinged to the first section. The arm is adapted at its other end to be pivotally attached to a fixture from said aperture. The fixture is in a plane which is parallel to that of the aperture.

Abstract: A roller chock for a boat. The chock includes an elongated base plate that mounts at the edge of a hull. A curved arm extends upwardly and aft to provide a smooth rubbing surface that is aligned with the general direction of a rode or other line. Spaced from the arm is a roller assembly having a top plate with portions extending forward and toward the center of the boat. A roller rotates with the line if it bends around the roller thereby to minimize wear on the line. The plate and the curved arm capture the line.