Abstract: Inflatable members for incorporation into a fascine are linked together at their ends by chains or other such flexible tension members, the tension in which is such as to cause at least local compression and flattening of the inflatable members where they are in contact with adjacent members. The forces so generated between adjacent members can prevent their tendency to rotate under the action of traffic crossing the fascine.

Abstract: An optical correlation apparatus is taught which provides a parallel optical signal having a phase modulation representing input data to which a parallel phase modulation based on reference data is applied. In the event of correlation the resulting wavefront is planar and can be interferometrically coupled to give a high intensity signal. The invention involves use of parallel amplitude modulation means for selectively blocking the optical signal in one or more of the channels of the parallel optical signal which allows different sized reference data strings to be searched more easily and also aids in calibration.

Abstract: An antenna system comprising an array of antenna elements, the array comprising a plurality of groups of antenna elements wherein each group comprises one or more antenna elements arranged in series, and wherein the system further comprises first phase-control means for performing the function of introducing respective phase-shifts to transmitted or received signals passed to or received from each of said groups to provide beamforming and second phase-control means for performing said function with respect to a sub-set of said groups. An antenna system of the invention allows two radar beam patterns having different spatial characteristics to be generated using a single antenna system. The invention also provides a radar system incorporating an antenna system of the invention.

Abstract: Traffic sensing and monitoring apparatus (100) comprises a length of optical fiber (112), means (102, 103, 104, 106, 107, 109, 119) arranged to introduce a series of pulse pairs into an input end of the length, each of the pulse pairs comprising first and second pulses of radiation having a frequency difference ? and the second pulse being delayed with respect to the first by a delay ?, and the apparatus further comprising a photodetector arranged to detect radiation which is Rayleigh-backscattered within the length of fiber towards the input end to generate an output signal in response thereto. Apparatus of the invention allows sensing and monitoring of traffic at any position along a long length of road (e.g. 5 km) with lower installation and maintenance costs per unit length compared to prior art systems providing the same spatial resolution.

Abstract: An imaging spectrometer is disclosed that comprises imaging means for dividing a received image into two or more spatially separated images and means for detecting each spectral image, and is characterized in that the imaging means comprises at least one polarizing beam splitter. The polarizing beam splitter may be a Wollaston prism. In one embodiment of the invention, the imaging means comprises image replication means to produce two or more spatially separated images, and one or more filter elements such as dichroic filters which act to alter the spectral characteristics of one or more of the spatially separated images. In a further embodiment of the invention the imaging means comprises one or more spectral replication means arranged in optical series, each spectral replication means comprising an optical retardation element and a polarizing beam splitter.

Abstract: A method of scoring Oestrogen and Progesterone Receptors expression (ER and PR) from histological images determines the percentage of brown image blob area in total blob area and derives percentage thresholds to quantify scoring. Brown blob area proportion is then compared with the thresholds to provide a first contribution to scoring of ER or PR. The number of relatively dark pixels is then counted, pixel number thresholds are determined to quantify scoring, and the number of relatively dark pixels is compared with the thresholds to provide a second contribution scoring of ER or PR. The two contributions are then added to provide an overall scoring in the range 0 to 8 which may be taken as a final score or it may be scaled to a conventional range 0 to 3.

Abstract: A method of detecting a target in a scene comprises the steps of generating a comparison of the value of data elements in first and second data sets, the data elements corresponding to returns from the same part of the scene and setting a detection threshold value for the comparison so as to detect targets entering said that part of scene The method provides improved target detection in the presence of clutter.

Abstract: A method of target recognition performs a 3D comparison of target and reference data. Translation invariant signatures are derived from the two data sets, and an estimate of the orientation of the target with respect to the reference is obtained. Rotational alignment and comparison can then be achieved. The 3D data sets can be represented on an axi-symmetric surface such as a sphere and rotational convolution, over a discrete set of selected rotation angles can be performed. Optic flow can be used to derive the estimate of orientation or the target relative to the reference, in terms of a displacement field.

Abstract: This invention relates to a method for determining the reply efficiency of a DME navigation beacon and to an apparatus for performing the method. The invention involves locating an RF receiver nearby a DME beacon to be tested. The RF receiver analyses all signals received on the interrogation frequency of that beacon to determine pulse pairs which correspond to a valid interrogation of that beacon. Other pulse events of interest may also be detected. The RF receiver also records all signals on the reply frequency of the beacon and detects all replies sent by the beacon. Particular interrogations can then be correlated with replies and the reply efficiency of the beacon determined. Several RF receivers may be located round the beacon to better provide correlation between particular interrogations and responses.

Abstract: An optical clock comprises a laser oscillator and modulating means arranged to cooperate with the laser oscillator to produce a series a series of phase-modulated optical pulses. The optical clock further comprises an optical fibre arranged to provide compression of the optical pulses, and may also comprise a step-recovery diode arranged to pulse-pick pulses output from the fibre to produce a series of optical clock pulses, depending on the mode of operation of the modulating means. Phase-modulation is carried out a frequency which provides sufficient linewidth broadening to inhibit stimulated Brillouin scattering within the optical fibre. An optical clock of the invention provides a robust and reliable alternative to clocks based on modelocked lasers, and may be assembled from inexpensive, commonly-available components. The repetition rate of a clock of the invention may easily be adjusted by electronic means. Unlike many modelocked lasers, a clock of the invention does not require precise optical alignment.

Abstract: A communications system incorporates a transmitter a receiver. The transmitter includes an infrared light emitting diode (LED). The LED output is positive or negative luminescence, i.e. above or below an equilibrium background intensity level respectively, according to the polarity of its bias signal. The receiver contains a lens to focus light from the LED onto a diode detector, from which signals pass to an amplifier, decoder and printer. Output signals from the LED have an average intensity equal to the equilibrium background intensity level and a frequency greater than 100 Hz or byte rate greater than 100 bytes/sec. They are not discernible by conventional thermal infrared imagers with frame rates of 50 Hz or less because integration in such an imager renders them indistinguishable from background.

Abstract: A vehicle arresting device comprises a net intended to be laid flat on the ground in the path of a target vehicle with an array of upwardly-directed spikes attached to the net along a leading portion, so that when a vehicle runs over the device some of the spikes engage in its front tires and the net is caused to wrap around the front wheels, being pulled tight under the vehicle to prevent further rotation of those wheels. There are two rows of spikes, with the spikes in the second row being substantially longer than the spikes in the leading row. The gauge of the netting also varies, with the leading strip which includes the shorter spikes and back towards the longer spikes being of a thinner gauge, the portion from the longer spikes back to approximately the mid length of the net being of a thicker gauge, and the trailing portion reverting to the thinner gauge. These measures help to ensure that the net is capable of arresting a wide range of vehicles, from passenger cars to trucks.

Abstract: An electric propulsion system including a plasma chamber having a first output aperture having first acceleration and screen grids, and a second output aperture having second acceleration and screen grids. The screen grids are maintained at a constant positive potential. In use, ions are expelled from the two apertures in anti-parallel directions. By independently controlling the potentials of the acceleration grids to adjust the rates of ion extraction from the output apertures, small resultant thrusts at the ?N level may be obtained and the resultant thrust maybe continuously reduced to zero. By closing off apertures of one of the screen grids, thrust at the mN may be obtained with sub-?N accuracy. The system therefore provides functionality previously achievable only with plural types of electric propulsion system, providing weight and complexity savings for satellites or space-probes comprising such systems.

Abstract: Reader apparatus for receiving data from a transponder in the body of a patient, for example a femoral nail. The apparatus includes an antenna which can be varied in size and shape to fit patients, the size and shape of whose bodies vary significantly. A variable impedance unit is included to maximise power matching between the antenna and a reader unit for a given antenna configuration.

Abstract: An electrode assembly is formed by respectively overlaying a sheet cathode 1, a sheet separator 3 and a double-sided sheet anode 8 to form a stacked structure 10, and subjecting the stacked structure to multiple folds, wherein the initial fold comprises folding the cathode in half around the double-sided anode so as to surround the respective upper and lower active anode surfaces thereof. The multiple folds may comprise one or more subsequent parallel folds made with the fold line D-D extending perpendicular to the original length of the stacked structure such that its overall length is halved at each fold. A pouch battery comprising said electrode assembly has improved safety and performance characteristics. The pouch battery construction has especial application to lithium primary batteries.

Abstract: A method of anomaly detection applicable to telecommunications or retail fraud or software vulnerabilities uses inductive logic programming to develop anomaly characterization rules from relevant background knowledge and a training data set, which includes positive anomaly samples of data covered by rules. Data samples include 1 or 0 indicating association or otherwise with anomalies. An anomaly is detected by a rule having condition set which the anomaly fu,lfils. Rules are developed by addition of conditions and unification of variables, and are filtered to remove duplicates, equivalents, symmetric rules and unnecessary conditions. Overfitting of noisy data is avoided by an encoding cost criterion. Termination of rule construction involves criteria of rule length, absence of negative examples, rule significance and accuracy, and absence of recent refinement.

Abstract: A molecular single electron transistor (MSET) detector device (14) is described that comprises at least one organic molecule (87) connecting a drain electrode (84) and a source electrode (82). In use, said at least one organic molecule (87) provides a quantum confinement region. At least one analyte receptor site (90, 92) is provided in the vicinity of said at least one organic molecule (87) that bind molecules of interest (analytes). A fluid analyser (2) is also described that includes the MSET detector, a pre-concentrator (4) and a fluid gating structure (6). The fluid gating structure (6) is arranged to selectively route fluid from the pre-concentrator (4) to either one of the detector (14) and an exhaust port (12). The pre-concentrator (4), fluid gating structure (6) and detector (14) are each formed as substantially planar layers and arranged in a stack or cube.

Abstract: A method of processing for a coded aperture imaging apparatus which is useful for target identification and tracking. The method uses a statistical scene model and, preferably using several frames of data, determines a likelihood of the position and/or velocity of one or more targets assumed to be in the scene. The method preferably applies a recursive Bayesian filter or Bayesian batch filter to determine a probability distribution of likely state parameters. The method acts upon the acquired data directly without requiring any processing to form an image.

Abstract: Method and apparatus for mitigating the effects of security threat involving malicious code concealed in computer files (for example computer viruses, etc.). The method operates by inserting additional strings of arbitrary length within computer files of known type which may contain such security threats. The strings are chosen to have no substantial effect on the files in normal operation, but potentially disrupt attack code located in the file. Inserted sequences may incorporate a character sequence which, if interpreted as code, halts execution of that program. Alternatively, or in addition, character sequences may be deleted or reordered provided that they have no effect on normal interpretation of the file. As a result, the effect of malicious code operating successfully as intended by an attacker may be mitigated. The methods do not require prior knowledge of the nature of a specific threat and so provide threat mitigation for previously unidentified threats.

Abstract: A barrier adapted to be set up for temporary traffic control comprises a man-portable unit placed on the ground from which a boom, preferably in the form of a reelable tube, can be withdrawn. The boom extends at an oblique angle to the ground in its “down” position and a motor within the ground-standing unit can raise and lower it between that position and an “up” position at a greater angle to the ground in which traffic can pass.