Abstract: An aircraft electrical network including a first starter generator mechanically coupled to a first shaft of an aircraft main engine. The first starter generator is configured to turn the first shaft of the main engine in a starting mode, and to generate electricity from the first shaft of the gas turbine engine in a generating mode. The network further includes a DC electrical bus electrical coupled to one or more electrical loads and an AC electrical bus electrically coupled to the first starter generator. The DC electrical bus is electrically coupled to the AC electrical bus via a bi-directional AC/DC converter, which is configured to provide AC electrical power from the DC electrical bus to power the first starter generator when the first starter generator is in a starting mode, and DC electrical power to the DC electrical bus when the first starter generator is in a generating mode.

Abstract: In general, techniques are described for advertising end user content delivery reachability by content delivery networks (CDNs) to upstream content serving entities. In one example, a CDN interconnection (CDNI) device of a content serving entity receives a prefix advertisement that specifies a downstream entity and indicates the downstream entity provides content delivery reachability to the network address prefix. A request router of the CDNI device receives a content request that includes a request for content and specifies a network address of an end user device to receive the content, wherein the network address is within a range defined by the network address prefix. The request router selects the downstream entity to serve the content request based at least on the content delivery reachability indication and redirects the content request to the downstream entity.

Abstract: An aircraft electrical network including a first starter generator mechanically coupled to a first shaft of an aircraft main engine. The first starter generator is configured to turn the first shaft of the main engine in a starting mode, and to generate electricity from the first shaft of the gas turbine engine in a generating mode. The network further includes a DC electrical bus electrical coupled to one or more electrical loads and an AC electrical bus electrically coupled to the first starter generator. The DC electrical bus is electrically coupled to the AC electrical bus via a bi-directional AC/DC converter, which is configured to provide AC electrical power from the DC electrical bus to power the first starter generator when the first starter generator is in a starting mode, and DC electrical power to the DC electrical bus when the first starter generator is in a generating mode.

Abstract: A sample of nonlinear optical material for use in a nonlinear optical device contains a grating comprising alternating regions of inverted and non-inverted nonlinear coefficient of the material, with the regions separated by boundaries positioned such that the grating can provide quasi-phase matching of a selected nonlinear optical interaction, and compensate for phase mismatch arising from the Gouy phase shift of one or more focused optical beams involved in the interaction. The boundary positions can be calculated for second harmonic generation or optical parametric generation and oscillation.

Abstract: A process for poling a ferroelectric material doped with a metal, which process comprises: (i) defining an electrode pattern on a ?z face of a crystal of the ferroelectric material doped with the metal; (ii) providing an electrode material; (iii) poling at a temperature of not more than 45° C.; and (iv) poling by a two-stage voltage-controlled application of electric field based on a first poling stage of domain nucleation and a second poling stage of domain spreading.

Abstract: A method of inducing a periodic variation of nonlinearity value in a sample of ferroelectric material comprises arranging a pair of electrodes on opposite faces of the sample, one electrode defining a desired pattern of nonlinearity variation, applying a pre-bias voltage across the sample for a predetermined time using the electrodes, the pre-bias voltage being less than the coercive field of the ferroelectric material; and after the predetermined time, applying a current-controlled poling voltage across the sample using the electrodes, to produce domain inversion in the sample according to the desired pattern of nonlinearity variation. The pre-bias voltage may be 75% of the coercive field or more, and applied for a pre-determined time between 1 and 100 seconds.

Abstract: User feedback regarding a displayed item, such as a web page, is obtained by providing a first and second transport-control elements, such as back buttons, that have the same effect for moving within or between displayable items but which have different associated semantic information. Upon activation of one of the transport-control elements, not only is the required movement effected, but data is output or stored indicative of the semantic information associated with the activated transport-control element. Thus, for example, the semantic information associated with one transport-control element can relate to a good user experience of the currently-displayed item whilst the semantic information associated with the other transport-control element can relate to a bad user experience of the displayed item. Related server arrangements and page and program code are also envisaged.

Abstract: A sample of nonlinear optical material for use in a nonlinear optical device contains a grating comprising alternating regions of inverted and non-inverted nonlinear coefficient of the material, with the regions separated by boundaries positioned such that the grating can provide quasi-phase matching of a selected nonlinear optical interaction, and compensate for phase mismatch arising from the Gouy phase shift of one or more focused optical beams involved in the interaction. The boundary positions can be calculated for second harmonic generation or optical parametric generation and oscillation.

Abstract: A method of inducing a periodic variation of nonlinearity value in a sample of ferroelectric material comprises arranging a pair of electrodes on opposite faces of the sample, one electrode defining a desired pattern of nonlinearity variation, applying a pre-bias voltage across the sample for a predetermined time using the electrodes, the pre-bias voltage being less than the coercive field of the ferroelectric material; and after the predetermined time, applying a current-controlled poling voltage across the sample using the electrodes, to produce domain inversion in the sample according to the desired pattern of nonlinearity variation. The pre-bias voltage may be 75% of the coercive field or more, and applied for a pre-determined time between 1 and 100 seconds.

Abstract: A process for poling a ferroelectric material doped with a metal, which process comprises: (i) defining an electrode pattern on a ?z face of a crystal of the ferroelectric material doped with the metal; (ii) providing an electrode material; (iii) poling at a temperature of not more than 45° C.; and (iv) poling by a two-stage voltage-controlled application of electric field based on a first poling stage of domain nucleation and a second poling stage of domain spreading.

Abstract: A method for controlling a computer entity to participate in a peer to peer network of a plurality of computer entities comprises, for each computer entity, operating a peer to peer protocol for enabling the computer entity to utilise resources of at least one other computer entity of the network, and for enabling at least one other computer entity of the network to utilise resources of the computer entity. Each computer entity is arranged to automatically operate a process for managing at least one other computer entity in the network, whenever the computer entity takes part in the peer to peer network using the peer to peer protocol.

Abstract: A method and apparatus is provided in which playable content is transmitted in response to a playable-content request; a key for the playable content is separately transmitted in response to a key request. Quality information about the playable content is used to generate tariff information from which a user charge is derived.

Abstract: A method of controlling access to playable content. The disclosed method includes receiving a request to access playable content having a plurality of associated access criteria, receiving a plurality of credentials, performing a matching process to compare the credentials to the access criteria, and allowing access to the playable content is permitted if the access criteria are met by a logical combination of the plurality of credentials.

Abstract: User feedback regarding a displayed item, such as a web page, is obtained by providing a first and second transport-control elements, such as back buttons, that have the same effect for moving within or between displayable items but which have different associated semantic information. Upon activation of one of the transport-control elements, not only is the required movement effected, but data is output or stored indicative of the semantic information associated with the activated transport-control element. Thus, for example, the semantic information associated with one transport-control element can relate to a good user experience of the currently-displayed item whilst the semantic information associated with the other transport-control element can relate to a bad user experience of the displayed item. Related server arrangements and page and program code are also envisaged.

Abstract: A method and apparatus is provided in which playable content is transmitted in response to a playable-content request; a key for the playable content is separately transmitted in response to a key request. Quality information about the playable content is used to generate tariff information from which a user charge is derived.

Abstract: A method of controlling access to playable content, the method comprising the steps of

Abstract: In order to facilitate the management of content items intended to be hosted by one or more content server systems, each item has associated behavior data that specifies a desired commercial behavior of that item as a function of at least one variable. The commercial behavior specified by the behavior data concerns, for example, placement, promotion or pricing of the content item. When a commercial decision is required concerning an item, its relevant behavior data, together with a current value of the said at least one variable concerned, is used to make the decision. By giving the content items their own autonomous behavior, the content provider is freed from being continually asked to make decisions regarding commercialization of the items.

Abstract: A method of enabling player device operation using a mobile communication device involves receiving an identifier on the mobile communication device from a provider system, transmitting the identifier from the mobile communication device to a player device to permit operation of the player device, and transmitting a continual signal from the mobile communication device to the player device to permit the player device to continue operation. Appropriate player devices, mobile communication devices and provider systems are described.