Patents by Inventor Angeliki Pantazi

Angeliki Pantazi 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).

  • Patent number: 10268949
    Abstract: Artificial neuron apparatus includes a resistive memory cell connected in an input circuit having a neuron input, for receiving neuron input signals, and a current source for supplying a read current to the cell. The input circuit is selectively configurable in response to a set of control signals, defining alternating read and write phases of operation, to apply the read current to the cell during the read phase and to apply a programming current to the cell, for programming cell resistance, on receipt of a neuron input signal during the write phase. The cell resistance is progressively changed from a first state to a second state in response to successive neuron input signals. The apparatus further includes an output circuit comprising a neuron output and a digital latch which is connected to the input circuit for receiving a measurement signal dependent on cell resistance.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: April 23, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Evangelos S. Eleftheriou, Lukas Kull, Angeliki Pantazi, Abu Sebastian, Milos Stanisavljevic, Tomas Tuma
  • Publication number: 20190108434
    Abstract: A neuromorphic architecture for a spiking neural network comprising a plurality of spiking neurons, each with a plurality of synapses and corresponding synaptic weights, the architecture further comprising a synaptic competition mechanism in connection with a spike-based learning mechanism based on spikes perceived behind a synapse, in which architecture synapses of different neurons connected to the same input compete for that input and based on the result of that competition, each neuron of the neural network develops an individual perception of the presented input spikes, the perception used by the learning mechanism to adjust the synaptic weights.
    Type: Application
    Filed: October 5, 2017
    Publication date: April 11, 2019
    Inventors: Stanislaw A. Wozniak, Angeliki Pantazi
  • Patent number: 10255942
    Abstract: A tape transport control system with enhanced regulation of tape tension and velocity over the entire length of the tape. For example, a closed-loop control system for controlling a tape transport includes circuitry adapted to output a signal representing a tape velocity at a tape head, circuitry adapted to output a signal representing a tape velocity at the first tape reel and a signal representing a tape velocity at the second tape reel, circuitry adapted to output a signal representing a tape tension, and circuitry adapted to, based on the received signals, generate control signals to control the tape velocity at least at one of the tape head, the first tape reel, the second tape reel, and the tension of the tape, using controller gains that depend on a longitudinal position of the tape, and to implement a system transfer function that is approximately independent of the longitudinal position.
    Type: Grant
    Filed: August 23, 2016
    Date of Patent: April 9, 2019
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Mark A. Lantz, Angeliki Pantazi
  • Patent number: 10217046
    Abstract: A neuromorphic processing device has a device input, for receiving an input data signal, and an assemblage of neuron circuits. Each neuron circuit comprises a resistive memory cell which is arranged to store a neuron state, indicated by cell resistance, and to receive neuron input signals for programming cell resistance to vary the neuron state, and a neuron output circuit for supplying a neuron output signal in response to cell resistance traversing a threshold. The device includes an input signal generator, connected to the device input and the assemblage of neuron circuits, for generating neuron input signals for the assemblage in dependence on the input data signal. The device further includes a device output circuit, connected to neuron output circuits of the assemblage, for producing a device output signal dependent on neuron output signals of the assemblage, whereby the processing device exploits stochasticity of resistive memory cells of the assemblage.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: February 26, 2019
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Evangelos S. Eleftheriou, Manuel Le Gallo, Angeliki Pantazi, Abu Sebastian, Tomas Tuma
  • Publication number: 20190057301
    Abstract: Neuromorphic processing apparatus is provided. The present invention may include a spiking neural network comprising a set of input spiking neurons each connected to each of a set of output spiking neurons via a respective synapse for storing a synaptic weight which is adjusted for that synapse in dependence on network operation in a learning mode of the apparatus, and each synapse is operable to provide a post-synaptic signal, dependent on its synaptic weight, to its respective output neuron. The present invention may further include a pre-processor unit adapted to process input data, defining a pattern of data points, to produce a first set of input spike signals which encode values representing respective data points, and a second set of input spike signals which encode values complementary to respective said values representing data points, and to supply the input spike signals to respective predetermined input neurons of the network.
    Type: Application
    Filed: August 17, 2017
    Publication date: February 21, 2019
    Inventors: Angeliki Pantazi, Severin Sidler, Stanislaw A. Wozniak
  • Publication number: 20180374508
    Abstract: Embodiments of the present invention provide a tape transport control system with enhanced regulation of tape tension and velocity over the entire length of the tape. The tape transport control system comprises of circuitry adapted to output and circuitry adapted to receive one or more signals representing a tape velocity, at least one radius of either the first tape reel or the second tape reel, and a tape tension, and based on the received signals, generate at least one control signal to control at least one of the first reel motor or the second reel motor so as to reduce a tension disturbance at a minimum, one frequency corresponding to a time-varying reel-rotation frequency, based on controller parameters that depend on the tape velocity and on the at least one radius of either the first tape reel or the second tape reel.
    Type: Application
    Filed: June 23, 2017
    Publication date: December 27, 2018
    Inventors: Angeliki Pantazi, Giovanni Cherubini, Tomoko Taketomi, Nhan X. Bui, Mark A. Lantz
  • Patent number: 10141016
    Abstract: A tape drive-implemented method, according to one embodiment, includes: determining a number of lateral position estimates to use for calculating a lateral position value, receiving lateral position estimates from a single servo channel, calculating the lateral position value by using the number of lateral position estimates, and using the lateral position value to control a tape head actuator. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Grant
    Filed: February 22, 2017
    Date of Patent: November 27, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Nhan X. Bui, Giovanni Cherubini, Simeon Furrer, Randy C. Inch, Mark A. Lantz, Angeliki Pantazi
  • Publication number: 20180240484
    Abstract: A tape drive-implemented method, according to one embodiment, includes: determining a number of lateral position estimates to use for calculating a lateral position value, receiving lateral position estimates from a single servo channel, calculating the lateral position value by using the number of lateral position estimates, and using the lateral position value to control a tape head actuator. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Application
    Filed: February 22, 2017
    Publication date: August 23, 2018
    Inventors: Nhan X. Bui, Giovanni Cherubini, Simeon Furrer, Randy C. Inch, Mark A. Lantz, Angeliki Pantazi
  • Patent number: 10037803
    Abstract: An apparatus for programming at least one multi-level Phase Change Memory (PCM) cell having a first terminal and a second terminal. A programmable control device controls the PCM cell to have a respective cell state by applying at least one current pulse to the PCM cell, the control device controlling the at least one current pulse by applying a respective first pulse to the first terminal and a respective second pulse applied to the second terminal of the PCM cell. The respective cell state is defined by a respective resistance level. The control device receives a reference resistance value defining a target resistance level for the cell, and further receives an actual resistance value of said PCM cell such that the applying the respective first pulse and said respective second pulse is based on said actual resistance value of the PCM cell and said received reference resistance value.
    Type: Grant
    Filed: December 29, 2016
    Date of Patent: July 31, 2018
    Assignee: HGST NETHERLANDS BV
    Inventors: Evangelos S. Eleftheriou, Angeliki Pantazi, Nikolaos Papandreou, Haris Pozidis, Abu Sebastian
  • Patent number: 9996793
    Abstract: Method to produce a neuromorphic synapse apparatus comprising a memelement for storing a synaptic weight, and programming logic. The memelement is adapted to exhibit a desired programming characteristic. The programming logic is responsive to a stimulus prompting update of the synaptic weight for generating a programming signal for programming the memelement to update said weight. The programming logic may be responsive to an input signal indicating an input weight-change value ?Wi, and may be adapted to generate a programming signal dependent on the input weight-change value ?Wi. The programming logic is adapted such that the programming signals exploit the programming characteristic of the memelement to provide a desired weight-dependent synaptic update efficacy.
    Type: Grant
    Filed: July 21, 2015
    Date of Patent: June 12, 2018
    Assignee: International Business Machines
    Inventors: Evangelos S. Eleftheriou, Manuel Le Gallo, Angeliki Pantazi, Abu Sebastian, Tuma Tomas
  • Patent number: 9990580
    Abstract: Neuromorphic synapse apparatus 11 comprises a memelement 20 for storing a synaptic weight, and programming logic 21. The memelement 20 is adapted to exhibit a desired programming characteristic. The programming logic 21 is responsive to a stimulus prompting update of the synaptic weight for generating a programming signal for programming the memelement 20 to update said weight. The programming logic 21 may be responsive to an input signal indicating an input weight-change value ?Wi, and may be adapted to generate a programming signal dependent on the input weight-change value ?Wi. The programming logic 21 is adapted such that the programming signals exploit the programming characteristic of the memelement 20 to provide a desired weight-dependent synaptic update efficacy.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: June 5, 2018
    Assignee: International Business Machines Corporation
    Inventors: Evangelos S. Eleftheriou, Manuel Le Gallo, Angeliki Pantazi, Abu Sebastian, Tuma Tomas
  • Patent number: 9964419
    Abstract: A sensor arrangement for position sensing comprises a magnetic field source and a magnetoresistive element arranged in a magnetic field generated by the magnetic field source, which magnetoresistive element provides an output signal (R) dependent on a position (x) of the magnetoresistive element relative to the magnetic field source. A feedback controller is configured to receive the output signal (R) of the magnetoresistive element and is configured to adjust one or more of the position (x) of the magnetoresistive element relative to the magnetic field source and a strength of the magnetic field generated by the magnetic field source acting on the magnetoresistive element dependent on the output signal (R) of the magnetoresistive element.
    Type: Grant
    Filed: January 17, 2017
    Date of Patent: May 8, 2018
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Angeliki Pantazi, Abu Sebastian, Tomas Tuma
  • Publication number: 20180120129
    Abstract: A sensor arrangement for position sensing comprises a row of multiple magnetoresistive elements. A magnetic field source (3) provides a magnetic field with a first magnetic pole (N) and a second magnetic pole (S). The magnetic field source (3) is arranged such that magnetoresistive elements of the row face one of: the first magnetic pole (N) or second magnetic pole (S). The first magnetoresistive element is arranged in the magnetic field and provides a first output signal dependent on a position of the magnetoresistive element relative to the magnetic field source (3). A measurement unit is configured to determine a position of the magnetic field source (3) relative to the magnetoresistive elements of the row dependent on the first output signals of the magnetoresistive elements.
    Type: Application
    Filed: December 27, 2017
    Publication date: May 3, 2018
    Inventors: Walter Haeberle, Angeliki Pantazi, Abu Sebastian, Tuma Tomas
  • Patent number: 9945693
    Abstract: A method for determining of a position of an object using a sensor arrangement that includes a first magnetoresistive element and a second magnetoresistive element. A source provides a magnetic field with first and second magnetic poles. The source is arranged between the first magnetoresistive element and the second magnetoresistive element with the first magnetic pole facing the first magnetoresistive element and the second magnetic pole facing the second magnetoresistive element. The first magnetoresistive element is arranged in the magnetic field and provides a first output signal dependent on a position of the first magnetoresistive element relative to the magnetic field source. The second magnetoresistive element is arranged in the magnetic field and provides a second output signal dependent on a position of the second magnetoresistive element relative to the magnetic field source.
    Type: Grant
    Filed: August 13, 2015
    Date of Patent: April 17, 2018
    Assignee: International Business Machines Corporation
    Inventors: Walter Haeberle, Angeliki Pantazi, Abu Sebastian, Tuma Tomas
  • Publication number: 20180075346
    Abstract: Embodiments relate to a neuromorphic architecture for unsupervised feature learning using memristive synapses realized using phase-change devices. A spiking neural network architecture for unsupervised pattern learning and a spike-based learning algorithm compatible with phase-change synapses is described, and a feature-learning algorithm capable of performing a sequence of set operations on input patterns is provided. A learning rule for the extraction of certain features of the input that is compatible with spiking neurons and synapses with spike-based plasticity is also provided. The system enables enhanced pattern- and feature-extraction capabilities in neuromorphic systems.
    Type: Application
    Filed: September 13, 2016
    Publication date: March 15, 2018
    Inventors: Angeliki Pantazi, Stanislaw Andrzej Wozniak
  • Publication number: 20180068217
    Abstract: Artificial neuron apparatus includes first and second resistive memory cells. The first resistive memory cell is connected in first circuitry having a first input and output. The second resistive memory cell is connected in second circuitry having a second input and output. The first and second circuitry are operable in alternating read and write phases to apply a programming current to their respective memory cells on receipt of excitatory and inhibitory neuron input signals, respectively. During the write phase, resistance of the respective cells is changed in response to successive excitatory and inhibitory neuron input signals. During the read phase, a read current is applied to their respective cells to produce first and second measurement signals, respectively. An output circuit connected to the first and second outputs produces a neuron output signal at a neuron output when a difference between the first and second measurement signals traverses a threshold.
    Type: Application
    Filed: September 7, 2016
    Publication date: March 8, 2018
    Inventors: Evangelos S. Eleftheriou, Lukas Kull, Manuel Le Gallo-Bourdeau, Angeliki Pantazi, Abu Sebastian, Tomas Tuma
  • Publication number: 20180061448
    Abstract: A tape transport control system with enhanced regulation of tape tension and velocity over the entire length of the tape. For example, a closed-loop control system for controlling a tape transport includes circuitry adapted to output a signal representing a tape velocity at a tape head, circuitry adapted to output a signal representing a tape velocity at the first tape reel and a signal representing a tape velocity at the second tape reel, circuitry adapted to output a signal representing a tape tension, and circuitry adapted to, based on the received signals, generate control signals to control the tape velocity at least at one of the tape head, the first tape reel, the second tape reel, and the tension of the tape, using controller gains that depend on a longitudinal position of the tape, and to implement a system transfer function that is approximately independent of the longitudinal position.
    Type: Application
    Filed: August 23, 2016
    Publication date: March 1, 2018
    Inventors: Giovanni Cherubini, Mark A. Lantz, Angeliki Pantazi
  • Publication number: 20170372194
    Abstract: This invention relates to an apparatus, system, and method for computing with neuromorphic circuit architectures that have neurons with interconnected internal state information. The interconnected internal state information allows the neurons to enable or strengthen the input to other neurons. Furthermore, neuron internal state information provides insights on the characteristics of the input data that can be used to enhance the performance of the neuromorphic system. The neuromorphic system can be implemented with an artificial phase-change-based neurons.
    Type: Application
    Filed: June 22, 2016
    Publication date: December 28, 2017
    Inventors: Angeliki Pantazi, Tomas Tuma, Stanislaw Wozniak
  • Publication number: 20170270404
    Abstract: Artificial neuron apparatus includes a resistive memory cell connected in an input circuit having a neuron input, for receiving neuron input signals, and a current source for supplying a read current to the cell. The input circuit is selectively configurable in response to a set of control signals, defining alternating read and write phases of operation, to apply the read current to the cell during the read phase and to apply a programming current to the cell, for programming cell resistance, on receipt of a neuron input signal during the write phase. The cell resistance is progressively changed from a first state to a second state in response to successive neuron input signals. The apparatus further includes an output circuit comprising a neuron output and a digital latch which is connected to the input circuit for receiving a measurement signal dependent on cell resistance.
    Type: Application
    Filed: March 21, 2016
    Publication date: September 21, 2017
    Inventors: Evangelos S. Eleftheriou, Lukas Kull, Angeliki Pantazi, Abu Sebastian, Milos Stanisavljevic, Tomas Tuma
  • Patent number: 9759578
    Abstract: A sensor arrangement for position sensing comprises a first magnetoresistive element (1) and a second magnetoresistive element (2). A magnetic field source (3) provides a magnetic field with a first magnetic pole (N) and a second magnetic pole (S). The magnetic field source (3) is arranged between the first magnetoresistive element (1) and the second magnetoresistive element (2) with the first magnetic pole (N) facing the first magnetoresistive element (1) and the second magnetic pole (S) facing the second magnetoresistive element (2). The first magnetoresistive element (1) is arranged in the magnetic field and provides a first output signal (R1) dependent on a position of the first magnetoresistive element (1) relative to the magnetic field source (3). The second magnetoresistive element (2) is arranged in the magnetic field and provides a second output signal (R2) dependent on a position of the second magnetoresistive element (2) relative to the magnetic field source (3).
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: September 12, 2017
    Assignee: International Business Machines Corporation
    Inventors: Walter Haeberle, Angeliki Pantazi, Abu Sebastian, Tuma Tomas