Patents by Inventor Stefan Hirschfeld

Stefan Hirschfeld 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: 20240096337
    Abstract: An encoder for providing an audio stream on the basis of a transform-domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. A decoder for providing a decoded representation of an audio signal on the basis of an encoded audio stream representing spectral components of frequency bands of the audio signal includes a noise filler for introducing noise into spectral components of a plurality of frequency bands to which separate frequency band gain information is associated on the basis of a common multi-band noise intensity value.
    Type: Application
    Filed: November 29, 2023
    Publication date: March 21, 2024
    Applicant: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung e.V.
    Inventors: Nikolaus RETTELBACH, Bernhard GRILL, Guillaume FUCHS, Stefan GEYERSBERGER, Markus MULTRUS, Harald POPP, Juergen HERRE, Stefan WABNIK, Gerald SCHULLER, Jens HIRSCHFELD
  • Publication number: 20240096338
    Abstract: An encoder for providing an audio stream on the basis of a transform-domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. A decoder for providing a decoded representation of an audio signal on the basis of an encoded audio stream representing spectral components of frequency bands of the audio signal includes a noise filler for introducing noise into spectral components of a plurality of frequency bands to which separate frequency band gain information is associated on the basis of a common multi-band noise intensity value.
    Type: Application
    Filed: November 29, 2023
    Publication date: March 21, 2024
    Applicant: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung e.V.
    Inventors: Nikolaus RETTELBACH, Bernhard GRILL, Guillaume FUCHS, Stefan GEYERSBERGER, Markus MULTRUS, Harald POPP, Juergen HERRE, Stefan WABNIK, Gerald SCHULLER, Jens HIRSCHFELD
  • Publication number: 20240052085
    Abstract: The invention relates to a method for producing isocyanate-terminated, urethane group-containing prepolymers, comprising reacting a reaction mixture that contains a stoichiometric excess of at least one aliphatic and/or cycloaliphatic diisocyanate and a polyol composition having an OH number >400, characterized in that the reaction mixture is mixed with a specific power input of 0.5 kW/m3 to 40 kW/m3, relative to the total volume of the reaction mixture.
    Type: Application
    Filed: December 9, 2021
    Publication date: February 15, 2024
    Applicant: Covestro Deutschland AG
    Inventors: Christoph Malbertz, Stefan Hirschfeld, Dieter Mager, Oswald Wilmes
  • Publication number: 20230271916
    Abstract: The invention relates to a method for preparing a suspension of a hydrochloride of an organic amine, comprising the following steps of (i) initially charging at least one organic solvent in a reaction vessel to form a liquid level, (ii) adding hydrogen chloride, (iii) adding the organic amine, wherein the organic amine is added below the liquid level present in the reaction vessel and steps (ii) and (iii) are at least partly carried out simultaneously. Furthermore, the present invention also relates to a method wherein the suspension obtained after step (iii) is reacted in a step (iv) with phosgene to obtain the organic isocyanate corresponding to the organic amine used, to the corresponding organic isocyanate and to the use of the organic isocyanate for producing polyisocyanates.
    Type: Application
    Filed: May 5, 2023
    Publication date: August 31, 2023
    Inventors: Michael Merkel, Tim Loddenkemper, Frank Gerhartz, Stefan Hirschfeld
  • Publication number: 20200392074
    Abstract: The invention relates to a method for preparing a suspension of a hydrochloride of an organic amine, comprising the following steps of (i) initially charging at least one organic solvent in a reaction vessel to form a liquid level, (ii) adding hydrogen chloride, (iii) adding the organic amine, wherein the organic amine is added below the liquid level present in the reaction vessel and steps (ii) and (iii) are at least partly carried out simultaneously. Furthermore, the present invention also relates to a method wherein the suspension obtained after step (iii) is reacted in a step (iv) with phosgene to obtain the organic isocyanate corresponding to the organic amine used, to the corresponding organic isocyanate and to the use of the organic isocyanate for producing polyisocyanates.
    Type: Application
    Filed: May 27, 2020
    Publication date: December 17, 2020
    Inventors: Michael Merkel, Tim Loddenkemper, Frank Gerhartz, Stefan Hirschfeld