Abstract: A loudspeaker comprises a region devoid of electroacoustic transducers and at least two groups of electroacoustic transducers at the periphery of the region. Each of the groups is configured to produce a different sound field representative of an audio signal and each of the groups comprise a different set of transducers. This allows a more compact loudspeaker to be provided because the transducers can be located around the periphery of a visual display screen. Sound quality is not compromised because groups of transducers forming a subset of the totality of transducers are used for each sound signal, thereby avoiding alias beams.

Abstract: This invention relates to transition metal catalyst compounds represented by the formula: LMX2 wherein M is a Group 7 to 11 metal; L is a tridentate or tetradentate neutrally charged ligand that is bonded to M by least three or four nitrogen atoms, and at least one terminal nitrogen atom is part of a pyridinyl ring, a different terminal nitrogen atom is substituted with one C3–C50 hydrocarbyl, and one hydrogen atom or two hydrocarbyls; wherein at least one hydrocarbyl is a C3–C50 hydrocarbyl, and the central nitrogen atom is bonded to at least three different carbon atoms or two different carbon atoms, and one hydrogen atom; X is independently a monoanionic ligand or both X are joined together to form a bidentate dianionic ligand.

Abstract: A method or apparatus for use in generating an information system, wherein an object-oriented model of the information system is provided, the model defining classes of information objects require to be supported by the information system in terms of their attributes, operations that maybe performed on the object, and an intended relationship (if any) between two or more of the objects. Built-in or predefined descriptions of the operations which maybe performed on the objects are provided in terms of conditions that should hold initially, data that might be affected, and the desired results. An operation referenced in a class definition is then automatically expanded by adding a respective built-in or predefined description thereto within the object-oriented model of the information system.

Abstract: This invention relates to a transition metal catalyst compound represented by the formula: LMX2 or (LMX2)2 wherein each M is independently a Group 7 to 11 metal, preferably a Group 7, 8, 9, or 10 metal; each L is, independently, a tridentate or tetradentate neutrally charged ligand that is bonded to M by three or four nitrogen atoms, (where at least one of the nitrogen atoms is a central nitrogen atom and at least two of the nitrogen atoms are terminal nitrogen atoms), and at least two terminal nitrogen atoms are substituted with one C3–C50 hydrocarbyl and one hydrogen atom or two hydrocarbyls wherein at least one hydrocarbyl is a C3–C50 hydrocarbyl, and the central nitrogen atom is bonded to three different carbon atoms or two different carbon atoms and one hydrogen atom; X is independently a monoanionic ligand, or two X may join together to form a bidentate dianionic ligand.

Abstract: A method for initiating transactions of traded instruments includes determining an available offered quantity of a first instrument that represents an amount of the first instrument currently available to be purchased. The method also includes determining an unavailable offered quantity of the first instrument that represents an amount of the first instrument specified by a sale order associated with a first transaction. The method further includes determining a bid quantity specified by a purchase order associated with the first transaction and calculating a temporarily unavailable offered quantity of the first instrument based on a difference between the unavailable offered quantity of the first instrument and the bid quantity.

Abstract: For digital underwater transmission an information sequence (17) of digital bits is partitioned into a succession of symbols each comprising n bits where n is equal to or greater than one (2n potential symbols), each symbol (19) is replaced (20) a corresponding base code sequence of length m bits and the result (21) is passed to an acoustic transducer after bi-phase modulation (22) on a carrier. The code has good correlation properties, e.g. a pseudo-random maixmal length sequence, a Gold code or a Kasami code, and the value of m/n is at least (32). Preferably the base sequence is cyclically extended at one or both ends prior to modulation, and Solomon Reed redundancy coding (18) is initially applied to the information sequence. The output (23) of modulator (22) may be prefaced (26) by a pair of chirp waveforms (24). Provision is made for Doppler and multi-path correction.

Abstract: A routing device for routing streams at a node in a packet transmission network receives a stream request, reads specified parameters and any values for loss and delay already incurred at preceding nodes in the network, or specified parameters as modified to take account of loss and delay already incurred at preceding nodes in the network, to determine in conjunction with existing streams already being handled by the routing device whether to accept or reject the stream, allocates one or more buffers to the stream if the stream request has been accepted, transmits the stream request with modified values for loss and delay, or with modified parameters to take account of loss and delay incurred at this and preceding nodes in the network if the stream request has been accepted, and returns a fail signal if the stream request has been rejected.

Abstract: In a digital acoustic transmission device in which a digital sequence (31) is electrically modulated (22) on a carrier cos ?t, the modulated carrier (23) is prefaced with at least two pulse signals (24) of known timing relative to each other and to the modulated digital sequence to provide an output signal (13) for acoustic transmission. The pulse signals indicate to receiver the start of a transmission, and contain Doppler information for resampling the modulated signal prior to demodulation. Where the information sequence is in encoded blocks of equal length, the relationship between successive blocks can be used to update the Doppler information for use with the following block. Channel information can also be derived from the pulse signals and/or blocks for raking the next part of the incoming signal. Preferably the pulse signals have good correlation characteristics. In the embodiments the pulse signals are an immediately successive identical pair of linearly rising chirps.

Abstract: This invention relates to a transition metal catalyst compound represented by the formula: LMX2 or (LMX2)2 wherein each M is independently a Group 7 to 11 metal, preferably a Group 7, 8, 9, or 10 metal; each L is, independently, a tridentate or tetradentate neutrally charged ligand that is bonded to M by three or four nitrogen atoms, (where at least one of the nitrogen atoms is a central nitrogen atom and at least two of the nitrogen atoms are terminal nitrogen atoms), and at least two terminal nitrogen atoms are substituted with one C3-C50 hydrocarbyl and one hydrogen atom or two hydrocarbyls wherein at least one hydrocarbyl is a C3-C50 hydrocarbyl, and the central nitrogen atom is bonded to three different carbon atoms or two different carbon atoms and one hydrogen atom; X is independently a monoanionic ligand, or two X may join together to form a bidentate dianionic ligand.

Abstract: A method of obtaining trace data with respect to a running software program includes accessing a method in a call stack, the call stack including a sequentially ordered list of methods called during the running of the software program. If the accessed method in the call stack falls between a minimum trace offset and a maximum trace offset where the minimum trace offset and the maximum trace offset define a trace window, obtaining trace data for the method and outputting it to an output stream which is then collected into a trace data storage. If the trace data in the trace data storage meets predetermined adaptation rules then changing the position in the call stack of at least one of the minimum trace offset and the maximum trace offset.

Abstract: This invention relates to transition metal catalyst compounds represented by the formula: LMX2 wherein M is a Group 7 to 11 metal, L is a tridentate or tetradentate neutrally charged ligand that is bonded to M by three or four nitrogen atoms, and at least one terminal nitrogen atom is part of a pyridinyl ring, a different terminal nitrogen atom is substituted with one C3-C50 hydrocarbyl, and one hydrogen atom or two hydrocarbyls; wherein at least one hydrocarbyl is a C3-C50 hydrocarbyl, and the central nitrogen atom is bonded to three different carbon atoms or two different carbon atoms, and one hydrogen atom; X is independently a monoanionic ligand or both X are joined together to form a bidentate dianionic ligand.

Abstract: There is disclosed a method and controller for controlling an information flow in a data transmission system including receiving a plurality of data packets. The method and controller also includes selectively discarding and/or selectively time-shifting the data packets in a predetermined manner to generate a modified information flow. The method and controller also includes selectively discarding and/or selectively time-shifting the data packets of the modified information flow to generate at least one further modified information flow. The further modified information flow may be obtained in a selected one of a plurality of parallel steps.

Abstract: A method of allocating a priority level in an information flow in a data transmission system including receiving a plurality of data packets and allocating a priority level to each data packet is provided with a controller employing such method. The priority level may be determined in accordance with determining a class of loss of the data packet and a class of service for the data packet. The priority level is also a function of the current load of the information flow. It has been established that the choice for each degree of freedom should preferably be made independently and concurrently. The invention, therefore, provides a method for performing such a composite choice.

Abstract: There is disclosed a method and controller for controlling an information flow in a data transmission system including receiving a plurality of data packets having a received packet length and at a received sample rate. The method and controller also includes determining a configured packet length for each data packet based on a configured service rate for each data packet. The method and controller may also include scheduling each data packet in accordance with a respective configured packet length.

Abstract: There is disclosed a method and controller for controlling an information flow in an acyclic data transmission system including receiving a plurality of data packets, and allocating a priority level for each data packet including a class of loss for the data packet and a class of urgency of service for the data packet. The method and controller also include servicing the data packets in accordance with the priority levels and outputting the data packets at a configured rate.

Abstract: The invention generally relates to a method and apparatus for taking an input signal, replicating it a number of times and modifying each of the replicas before routing them to respective output transducers such that a desired sound field is created. This sound field may comprise a directed beam, focussed beam or a simulated origin. In a first aspect, delays are added to sound channels to remove the effects of different travelling distances. In a second aspect, a delay is added to a video signal to account for the delays added to the sound channels. In a third aspect, different window functions are applied to each channel to give improved flexibility of use. In a fourth aspect, a smaller extent of transducers is used top output high frequencies than are used to output low frequencies. An array having a larger density of transducers near the centre is also provided. In a fifth aspect, a line of elongate transducers is provided to give good directivity in a plane.

Abstract: An apparatus for modulating information bearing symbols onto an optical carrier includes a polybinary coder that operates on a binary information signal to produce an envelope compatible polybinary signal; and an optical single sideband modulator that modulates an optical carrier with the envelope compatible polybinary signal to produce a single sideband optical signal. This provides an improvement over both polybinary signaling and optical single sideband. This action combines the chromatic dispersion advantages of SSB modulation with the DC level and bandwidth reduction of duo-binary coding.

Abstract: For digital underwater transmission an information sequence (17) of digital bits is partitioned into a succession of symbols each comprising n bits where n is equal to or greater than one (2n potential symbols), each symbol (19) is replaced (20) with a corresponding base code sequence of length m bits and the result (21) is passed to an acoustic transducer after bi-phase modulation (22) on a carrier. The code has good correlation properties, e.g. a pseudo-random maixmal length sequence, a Gold code or a Kasami code, and the value of m/n is at least (32). Preferably the base sequence is cyclically extended at one or both ends prior to modulation, and Solomon Reed redundancy coding (18) is initially applied to the information sequence. The output (23) of modulator (22) may be prefaced (26) by a pair of chirp waveforms (24). Provision is made for Doppler and multi-path correction.