Patents by Inventor Duncan A MacDougall

Duncan A MacDougall has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20210215103
    Abstract: A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.
    Type: Application
    Filed: March 31, 2021
    Publication date: July 15, 2021
    Applicant: ROLLS-ROYCE PLC
    Inventors: Ian J BOUSFIELD, Duncan A MACDOUGALL
  • Patent number: 11047311
    Abstract: A core duct assembly for a gas turbine engine, the core duct assembly including: a core duct including an outer and an inner wall, the outer wall having an interior surface; a gas flow path member extending across the gas flow path at least partly between the inner and outer walls, the rotor blade having a radial span extending from a blade platform to a blade tip, wherein an upstream wall axis is defined as an axis tangential to a point on a first portion of the interior surface of the outer wall of the core duct extending downstream from the gas flow path member, the upstream wall axis lying in a longitudinal plane of the gas turbine engine containing the rotational axis of the engine, and wherein the upstream wall axis intersects the rotor blade at a point spaced radially inward from the blade tip of the rotor blade.
    Type: Grant
    Filed: June 11, 2019
    Date of Patent: June 29, 2021
    Assignee: ROLLS-ROYCE plc
    Inventors: Ian J Bousfield, Duncan A MacDougall
  • Patent number: 11002149
    Abstract: A gas turbine engine includes a fan mounted to rotate about a main longitudinal axis; an engine core, including a compressor, a combustor, and turbine coupled to the compressor through a shaft; and reduction gearbox; wherein the compressor includes a plurality of stages, each stage including a respective rotor and stator, a first stage of the plurality of stages being arranged at an inlet and including a first rotor with a plurality of blades; each blade extending chordwise from a leading edge to a trailing edge, and from root to tip for a span height, wherein 0% of the span height corresponds to the root and 100% of span height corresponds to tip; wherein the ratio of a maximum leading edge radius of the first rotor blades to a minimum leading edge radius of the first rotor blades is included between 2.2 and 3.5.
    Type: Grant
    Filed: June 11, 2019
    Date of Patent: May 11, 2021
    Assignee: ROLLS-ROYCE plc
    Inventors: Ian J Bousfield, Duncan A MacDougall
  • Patent number: 10995677
    Abstract: A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.
    Type: Grant
    Filed: March 10, 2020
    Date of Patent: May 4, 2021
    Assignee: ROLLS-ROYCE PLC
    Inventors: Ian J Bousfield, Duncan A Macdougall
  • Patent number: 10885215
    Abstract: A method and apparatus of a device searches encrypted objects stored in a secure virtual storage space is described. In an exemplary embodiment, the device receives a search query that includes a set of tokens and encrypts the set of tokens. The device further creates a hashed set of encrypted tokens using a second hash function. In addition, the device sends the hashed set of encrypted tokens to a first search server as a query. Furthermore, the device receives, from the first search server, a first set of encrypted object names as a search result. The device additionally determines a set of client-side indexes to search by hashing at least some of the first set of encrypted object names using a first hash function. The device further decrypts the set of encrypted object names. The additionally searches the set of client-side indexes using the set of decrypted object names.
    Type: Grant
    Filed: November 13, 2017
    Date of Patent: January 5, 2021
    Inventor: Duncan MacDougall Greatwood
  • Publication number: 20200347786
    Abstract: A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.
    Type: Application
    Filed: March 10, 2020
    Publication date: November 5, 2020
    Applicant: ROLLS-ROYCE PLC
    Inventors: Ian J BOUSFIELD, Duncan A MACDOUGALL
  • Publication number: 20200291862
    Abstract: A core duct assembly for a gas turbine engine, the core duct assembly including: a core duct including an outer and an inner wall, the outer wall having an interior surface; a gas flow path member extending across the gas flow path at least partly between the inner and outer walls, the rotor blade having a radial span extending from a blade platform to a blade tip, wherein an upstream wall axis is defined as an axis tangential to a point on a first portion of the interior surface of the outer wall of the core duct extending downstream from the gas flow path member, the upstream wall axis lying in a longitudinal plane of the gas turbine engine containing the rotational axis of the engine, and wherein the upstream wall axis intersects the rotor blade at a point spaced radially inward from the blade tip of the rotor blade.
    Type: Application
    Filed: June 11, 2019
    Publication date: September 17, 2020
    Applicant: ROLLS-ROYCE plc
    Inventors: Ian J. BOUSFIELD, Duncan A. MACDOUGALL
  • Publication number: 20200271012
    Abstract: A gas turbine engine includes a fan mounted to rotate about a main longitudinal axis; an engine core, including a compressor, a combustor, and turbine coupled to the compressor through a shaft; and reduction gearbox; wherein the compressor includes a plurality of stages, each stage including a respective rotor and stator, a first stage of the plurality of stages being arranged at an inlet and including a first rotor with a plurality of blades; each blade extending chordwise from a leading edge to a trailing edges, and from root to tip for a span height, wherein 0% of the span height corresponds to the root and 100% of span height corresponds to tip; wherein the ratio of a maximum leading edge radius of curvature of the first rotor blades to a minimum leading edge radius of curvature of the first rotor blades is included between 2.2 and 3.5.
    Type: Application
    Filed: June 11, 2019
    Publication date: August 27, 2020
    Applicant: ROLLS-ROYCE plc
    Inventors: Ian J. BOUSFIELD, Duncan A. MACDOUGALL
  • Patent number: 10671742
    Abstract: A method and apparatus of a device that stores an object on a plurality of storage servers is described. In an exemplary embodiment, the device shares an object between a first user and a second user stored in a secure virtual storage space. In this embodiment, the device storing an object in a secure virtual storage space, where the object is encrypted using an object key and is stored as a first plurality of different randomized bit vectors stored in a first plurality of storage servers in the secure virtual storage space. In addition, the device retrieves a private first user key from a client and retrieves a public second user key from the secure virtual storage space. Furthermore, the device creates a datagram key from the private first user key and the public second user key. The device additionally encrypts the object key using the datagram key to generate a datagram.
    Type: Grant
    Filed: November 13, 2017
    Date of Patent: June 2, 2020
    Inventor: Duncan MacDougall Greatwood
  • Patent number: 10612471
    Abstract: A gas turbine engine comprises a fan mounted to rotate about a main longitudinal axis; an engine core, comprising in axial flow series a compressor, a combustor, and a turbine coupled to the compressor through a shaft; a reduction gearbox that receives an input from the shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the shaft; wherein the compressor comprises a first stage at an inlet and a second stage, downstream of the first stage, comprising respectively a first rotor with a row of first blades and a second rotor with a row of second blades, the first and second blades comprising respective leading edges, trailing edges and tips, and wherein the ratio of a maximum leading edge radius of the first blades to a maximum leading edge radius of the second blades is greater than 2.8.
    Type: Grant
    Filed: November 18, 2019
    Date of Patent: April 7, 2020
    Assignee: ROLLS-ROYCE plc
    Inventors: Ian J Bousfield, Duncan A MacDougall
  • Patent number: 10578027
    Abstract: A gas turbine engine includes a fan, compressor, combustor, and turbine coupled to the compressor through a shaft. The compressor includes first, second, and third stages with respective rotor blades and stator vanes. The rotor blades and stator vanes are arranged such that a sum of mid-span axial gaps between the trailing edge of the first rotor blades and the leading edge of the first stator vanes, the trailing edge of the first stator vanes and the leading edge of the second rotor blades, the trailing edge of the second rotor blades and the leading edge of the second stator vanes, and the trailing edge of the second stator vanes and the leading edge of the third rotor blades is equal to a × inlet ? ? flow ? ? function 10 . ? a ? 75 ? ? mm ? ? and ? ? the ? ? inlet ? ? flow ? ? function = m ? T P .
    Type: Grant
    Filed: May 14, 2019
    Date of Patent: March 3, 2020
    Assignee: ROLLS-ROYCE plc
    Inventors: Duncan A MacDougall, Ian J Bousfield
  • Publication number: 20180150641
    Abstract: A method and apparatus of a device that stores an object on a plurality of storage servers is described. In an exemplary embodiment, the device shares an object between a first user and a second user stored in a secure virtual storage space. In this embodiment, the device storing an object in a secure virtual storage space, where the object is encrypted using an object key and is stored as a first plurality of different randomized bit vectors stored in a first plurality of storage servers in the secure virtual storage space. In addition, the device retrieves a private first user key from a client and retrieves a public second user key from the secure virtual storage space. Furthermore, the device creates a datagram key from the private first user key and the public second user key. The device additionally encrypts the object key using the datagram key to generate a datagram.
    Type: Application
    Filed: November 13, 2017
    Publication date: May 31, 2018
    Inventor: Duncan MacDougall Greatwood
  • Publication number: 20180145826
    Abstract: A method and apparatus of a device that stores an object on a plurality of storage servers is described. In an exemplary embodiment, the device receives an object to be stored and encrypts the object with a first key. The device further creates a plurality of bit vectors from the encrypted object. In addition, the device randomizes the plurality of bit vectors to generate a plurality of randomized bit vectors. Furthermore, the device sends the plurality of randomized bit vectors and the plurality of second keys to the plurality of storage servers, wherein each of the plurality of storage servers stores at least one each of the plurality of randomized bit vectors and the plurality of second keys.
    Type: Application
    Filed: November 13, 2017
    Publication date: May 24, 2018
    Inventor: Duncan MacDougall Greatwood
  • Publication number: 20180144152
    Abstract: A method and apparatus of a device searches encrypted objects stored in a secure virtual storage space is described. In an exemplary embodiment, the device receives a search query that includes a set of tokens and encrypts the set of tokens. The device further creates a hashed set of encrypted tokens using a second hash function. In addition, the device sends the hashed set of encrypted tokens to a first search server as a query. Furthermore, the device receives, from the first search server, a first set of encrypted object names as a search result. The device additionally determines a set of client-side indexes to search by hashing at least some of the first set of encrypted object names using a first hash function. The device further decrypts the set of encrypted object names. The additionally searches the set of client-side indexes using the set of decrypted object names.
    Type: Application
    Filed: November 13, 2017
    Publication date: May 24, 2018
    Inventor: Duncan MacDougall Greatwood
  • Publication number: 20170043850
    Abstract: The present invention relates to a life jacket. The life jacket comprises a floatable rope and securing means attached to the life jacket. The floatable rope extends from the securing means and is arranged such that it is suitable for attachment to lifting means.
    Type: Application
    Filed: April 23, 2015
    Publication date: February 16, 2017
    Applicant: Livesavers Limited
    Inventor: Duncan MacDougall (aka Duncan Wells)
  • Patent number: 8171061
    Abstract: A system and method for storing workgroup objects on a file-system based data store in a workgroup server is disclosed. The present invention implements a file-system based workgroup system in which a workgroup object is stored in one or more files. The present invention further includes a workgroup object list comprising object identifiers, each object identifier uniquely mapping to a workgroup object and each object identifier including a property of the workgroup object based on which the workgroup object list is sorted.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: May 1, 2012
    Assignee: Cisco Technology, Inc.
    Inventor: Duncan MacDougall Greatwood
  • Publication number: 20100023596
    Abstract: A system and method for storing workgroup objects on a file-system based data store in a workgroup server is disclosed. The present invention implements a file-system based workgroup system in which a workgroup object is stored in one or more files. The present invention further includes a workgroup object list comprising object identifiers, each object identifier uniquely mapping to a workgroup object and each object identifier including a property of the workgroup object based on which the workgroup object list is sorted.
    Type: Application
    Filed: December 14, 2006
    Publication date: January 28, 2010
    Applicant: POSTPATH, INC.
    Inventor: Duncan MacDougall Greatwood
  • Patent number: 6101553
    Abstract: A communication network end station is constituted by a host device including a processor and a memory; a bus; and a communication network interface device connected to the host device via the bus and, in use, to a communication network along which data is transmitted in accordance with a network protocol. The communication network interface device includes a processor which transfers data to and from the network in accordance with the network protocol. The control code for operating the processor is stored in the host device memory. The processor is adapted to route incoming data and associated network protocol information, as it is received, to the host device memory. The bus is capable of transmitting data and associated network protocol information at a speed compatible with the operating speed of the communication network.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: August 8, 2000
    Assignee: Madge Networks Limited
    Inventors: Duncan MacDougall Greatwood, Nicholas Ian Moss