Abstract: A combustion staging system for fuel burners of a multi-stage combustor of a gas turbine engine is provided. The system has pilot and mains fuel manifolds respectively distributing fuel to pilot and mains stages of the burners. The system further has a plurality of check valves through which the mains manifold feeds fuel to the respective burners. The check valves are arranged to open when the fuel pressure within the mains manifold exceeds a predetermined fuel pressure relative to gas pressure in the combustor. The system further has a splitting unit which receives a metered fuel flow and controllably splits the received fuel flow into pilot and mains flows which are sent respectively to the pilot and mains fuel manifolds to perform staging control of the combustor. The splitting unit is operable to select the pilot manifold and to deselect the mains manifold for pilot-only operation in which there is a pilot supply to the combustor but no mains supply to the combustor from the burners.

Abstract: A combustion staging system for fuel injectors of a multi-stage combustor of a gas turbine engine has pilot and mains fuel manifolds distributing fuel to the injectors. A splitting unit splits a fuel flow and sends portions of the flow to pilot and mains fuel manifolds to perform staging control of the combustor. The splitting unit can deselect the mains manifold so that there is no flow into the combustor from the mains manifold. A cooling flow recirculation line provides a cooling flow of fuel to the mains manifold when that manifold is deselected so that the mains manifold remains primed with relatively cool fuel. A return section collects the cooling flow from the mains manifold. One or more fuel pressure sensors detect pressure of the cooling flow on the recirculation line. A control arrangement closes off the recirculation line when the pressure sensor(s) indicates failure of the cooling flow.

Abstract: A combustion staging system for fuel burners of a multi-stage combustor of a gas turbine engine is provided. The system has pilot and mains fuel manifolds respectively distributing fuel to pilot and mains stages of the burners. The system further has a plurality of check valves through which the mains manifold feeds fuel to the respective burners. The check valves are arranged to open when the fuel pressure within the mains manifold exceeds a predetermined fuel pressure relative to gas pressure in the combustor. The system further has a splitting unit which receives a metered fuel flow and controllably splits the received fuel flow into pilot and mains flows which are sent respectively to the pilot and mains fuel manifolds to perform staging control of the combustor. The splitting unit is operable to select the pilot manifold and to deselect the mains manifold for pilot-only operation in which there is a pilot supply to the combustor but no mains supply to the combustor from the burners.

Abstract: A combustion staging system for fuel injectors of a multi-stage combustor of a gas turbine engine has pilot and mains fuel manifolds distributing fuel to the injectors. A splitting unit splits a fuel flow and sends portions of the flow to pilot and mains fuel manifolds to perform staging control of the combustor. The splitting unit can deselect the mains manifold so that there is no flow into the combustor from the mains manifold. A cooling flow recirculation line provides a cooling flow of fuel to the mains manifold when that manifold is deselected so that the mains manifold remains primed with relatively cool fuel. A return section collects the cooling flow from the mains manifold. One or more fuel pressure sensors detect pressure of the cooling flow on the recirculation line. A control arrangement closes off the recirculation line when the pressure sensor(s) indicates failure of the cooling flow.

Abstract: A method of manufacturing a multi-tooth fir-tree or bulbous form milling cutter, by the grinding of a blank with a grinding wheel, wherein, a flat clearance angle ? of between 0° and 20° is generated on each tooth (13) by the path (14) of the grinding wheel (10), with each tooth (13) having a width (X) from tip to point of maximum clearance (see FIG. 5), calculated as follows: —X={[(R tan ?)cos ?] cos ?}±0.25% (being calculation (A)) where R=radius of cutter, and where ?=clearance angle measured from a tangent to the tooth tip, and furthermore, wherein, each tooth (13) has a variable depth (Y) around the cutter, calculated as follows: —Y={[?D]/[180/?]}0.5±0.2. (being calculation (B)) where D=maximum diameter of the form at any given point along the form. The invention also includes fir tree and bulbous milling cutters produced by the above defined method.

Abstract: A method of manufacturing a multi-tooth fir-tree or bulbous form milling cutter, by the grinding of a blank with a grinding wheel, wherein, a flat clearance angle ? of between 0° and 20° is generated on each tooth (13) by the path (14) of the grinding wheel (10), with each tooth (13) having a width (X) from tip to point of maximum clearance (see FIG. 5), calculated as follows: X={[(Rtan?)cos?]cos?}±0.25% (being calculation (A)) where R=radius of cutter, and where ?=clearance angle measured from a tangent to the tooth tip, and furthermore, wherein, each tooth (13) has a variable depth (Y) around the cutter, calculated as follows: Y={[?D]/[180/?]} 0.5±0.2. (being calculation (B)) where D=maximum diameter of the form at any given point along the form. The invention also includes fir tree and bulbous milling cutters produced by the above defined method.

Abstract: A software architecture and control protocol that provides seamless playback of multiple clips of media data across a data network. Conventional server-based data network architecture where playback logic resides on the servers does not provide the capability of seamless playback of multiple clips stored in different servers. The present invention allows users to specify a playlist and provides control on the client with the implementation of a “client pull” data transport model. According to the present invention, the playlist is translated into a plurality of frame accurate requests, which are sent from the client to the servers one request at a time. The servers, upon receiving the requests, retrieve the corresponding frames of media data and transmit the media data back to the client. In this way, the present invention allows a user-interface to provide seamless playback of multiple clips that reside on different servers on the client workstation.

Abstract: A clearance control apparatus for controlling the clearance between a rotary assembly (17) and a casing (24) surrounding the rotary assembly (17) is disclosed. The clearance control apparatus comprises a temperature measuring device (34) to measure the temperature of a radially outer portion of the rotary assembly and a cooling arrangement (28) to cool the casing (24). A control system (36) is associated with the temperature measuring device (34) and the cooling arrangement (28) to control the extent of cooling of the casing (24). The extent of cooling is dependent upon the temperature of the aforesaid portion.

Abstract: A novel method and apparatus for protection of streamed media content is disclosed. In one aspect, the apparatus includes control means for governance of content streams or content objects, decryption means for decrypting content streams or content objects under control of the control means, and feedback means for tracking actual use of content streams or content objects. The control means may operate in accordance with rules received as part of the streamed content, or through a side-band channel. The rules may specify allowed uses of the content, including whether or not the content can be copied or transferred, and whether and under what circumstances received content may be “checked-out” of one device and used in a second device. The rules may also include or specify budgets, and a requirement that audit information be collected and/or transmitted to an external server. In a different aspect, the apparatus may include a media player designed to call plugins to assist in rendering content.

Abstract: A novel method and apparatus for protection of streamed media content is disclosed. In one aspect, the apparatus includes control means for governance of content streams or content objects, decryption means for decrypting content streams or content objects under control of the control means, and feedback means for tracking actual use of content streams or content objects. The control means may operate in accordance with rules received as part of the streamed content, or through a side-band channel. The rules may specify allowed uses of the content, including whether or not the content can be copied or transferred, and whether and under what circumstances received content may be “checked out” of one device and used in a second device. The rules may also include or specify budgets, and a requirement that audit information be collected and/or transmitted to an external server. In a different aspect, the apparatus may include a media player designed to call plugins to assist in rendering content.

Abstract: A process for scheduling operations using a cost function is provided. A number of scheduling options are determined for an operation and a cost is computed for each scheduling option. The process then schedules the operation based on a computed cost.

Abstract: A disc component for a gas turbine engine is produced from a workpiece by a sequence of machining operations. During the machining operations, the workpiece is supported by a fixture engaging support surfaces. The workpiece remains secured to the fixture throughout the sequence of machining operations so that these operations can be conducted on both faces of a disc portion of the workpiece without removing the workpiece from the fixture. The machining operations are conducted alternately on the opposite faces in order to allow residual stresses in the workpiece to dissipate in a controlled manner.

Abstract: Protection of digital content using a specific application of block cipher cryptography is described. The digital content is encrypted using an encryption key and a calculated initialization vector. The digital content includes a plurality of strides of data and each stride includes a string of data to be encrypted and a block of data to be encrypted. The calculated initialization vector to be used to encrypt the block of data is derived from the string of data in the stride to be encrypted. Furthermore, the initialization vector is calculated by performing an exclusive disjunction function on a seed value and the string of data for each stride.

Abstract: Protection of digital content using a specific application of block cipher cryptography is described. The digital content is encrypted using an encryption key and a calculated initialization vector. The digital content includes a plurality of strides of data and each stride includes a string of data to be encrypted and a block of data to be encrypted. The calculated initialization vector to be used to encrypt the block of data is derived from the string of data in the stride to be encrypted. Furthermore, the initialization vector is calculated by performing an exclusive disjunction function on a seed value and the string of data for each stride.

Abstract: A composite insulator containing means for providing early warning of impending failure due to stress corrosion cracking, flashunder, or destruction of the rod by discharge activity conditions is described. A composite insulator comprising a fiberglass rod surrounded by a polymer housing and connected with metal end fittings on either end of the rod is doped with a dye-based chemical dopant. The dopant is located around the vicinity of the outer surface of the fiberglass rod. The dopant is formulated to possess migration and diffusion characteristics, and to be inert in dry conditions and compatible with the insulator components. The dopant is positioned within the insulator such that upon the penetration of moisture through the housing to the rod through a permeation pathway in the outer surface of the insulator, the dopant will become activated and will leach out of the same permeation pathway or diffuse through the housing.

Abstract: A method of controlling the printing of graphic enhancements to a POS receipt using additional configuration commands. The method is implemented in a POS printer by designating exception byte strings (i.e., not usual text in receipts) to act as triggers for the suspension of the normal launching of a selected graphic function for a given number of iterations. The method also involves optionally eliminating the triggering text itself, as well as suspending the targeted graphic. The method does not require any changes to existing host software, such as the store checkout legacy application. Instead, byte string triggers are defined in the input text comprising the POS receipt and used to trigger suppression of the graphics normally merged with the legacy receipt output, thus allowing users to configure new custom control commands in the printer without having to upgrade or replace the legacy host application.