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Now showing items 8-27 of 619

    • Accelerated commutation for passive clamp isolated boost converters 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Lai, Jih-Sheng; Zhu, Lizhi (United States Patent and Trademark Office, 2005-04-05)
      An efficient and cost effective bidirectional DC/DC converter reduces switch voltage stress via accelerated commutation allowing use of a low-cost passive clamp circuit in boost mode. The converter includes a primary ...
    • Accessible kiosk 

      Virginia Tech Intellectual Properties, Inc.; Honaker, Andrew B.; Pasqualino, III, Philip P. (United States Patent and Trademark Office, 1999-06-01)
    • Accurate magnetic field sensor and method for wireless phasor measurement unit 

      Virginia Polytechnic Institute and State University; Liu, Yilu; Zhang, Guorui; Zhang, Yingchen (United States Patent and Trademark Office, 2013-05-07)
      A phasor measurement unit and method including a transducer for transduction measurement of an electrical characteristic of a current carrying element in electrical power generation or distribution systems, the transducer ...
    • Acousto-fluidic driver for active control of turbofan engine noise 

      Virginia Tech Intellectual Properties, Inc.; Defense Research Technologies, Inc.; Drzewiecki, Tadeusz M.; Fuller, Christopher R.; Burdisso, Ricardo A.; Thomas, Russell H.; Niemczuk, John B. (United States Patent and Trademark Office, 1997-09-02)
      Reduction or cancellation of acoustic noise is achieved by providing an amplified, oppositely phased version of the noise by means of an acousto-fluidic amplifier. The amplified acoustic output noise is delivered through ...
    • Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors 

      Center for Innovative Technology; Virginia Polytechnic Institute and State University; Virginia Tech Intellectual Properties, Inc.; Burdisso, Ricardo A.; Fuller, Chris R.; O'Brien, Walter F.; Thomas, Russell H.; Dungan, Mary E. (United States Patent and Trademark Office, 1996-05-07)
      An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi ...
    • Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors 

      Center for Innovative Technology; Virginia Polytechnic Institute and State University; Virginia Tech Intellectual Properties, Inc.; Burdisso, Ricardo A.; Fuller, Chris R.; O'Brien, Walter F.; Thomas, Russell H.; Dungan, Mary E. (United States Patent and Trademark Office, 1994-10-11)
      An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi ...
    • Active dual reaction mass absorber for vibration control 

      Virginia Tech Intellectual Properties, Inc.; Burdisso, Ricardo A.; Heilmann, John D. (United States Patent and Trademark Office, 1999-03-23)
      An active vibration absorber including a frame connected to a structure to be controlled and at least two reaction mass elements operatively connected to the frame. Each of the reaction mass elements is independently movable ...
    • Active/passive distributed absorber for vibration and sound radiation control 

      Virginia Tech Intellectual Properties, Inc.; Fuller, Christopher R.; Cambou, Pierre E. (United States Patent and Trademark Office, 2004-03-02)
      The active/passive absorber for extended vibration and sound radiation control includes principally two layers. The first layer has a low stiffness per unit area which allows motion in the direction perpendicular to its ...
    • Active/passive distributed absorber for vibration and sound radiation control 

      Virginia Tech Intellectual Properties, Inc.; Fuller, Christopher R.; Kondylas, Kathleen (United States Patent and Trademark Office, 2010-05-11)
      Vibration or acoustic sound control is achieved using an elastic layer of thermal or insulation material in which a plurality of discrete masses are distributed throughout. The elastic layer may be installed as a pre-formed ...
    • Active/passive distributed absorber for vibration and sound radiation control 

      Virginia Tech Intellectual Properties, Inc.; Fuller, Christopher R.; Kondylas, Kathleen (United States Patent and Trademark Office, 2009-08-11)
      The active/passive absorber for extended vibration and sound radiation control includes principally two layers. The first layer has a low stiffness per unit area which allows motion in the direction perpendicular to its ...
    • Active/passive distributed absorber for vibration and sound radiation control 

      Virginia Tech Intellectual Properties, Inc.; Fuller, Christopher R.; Cambou, Pierre E. (United States Patent and Trademark Office, 2005-10-25)
      The active/passive absorber for extended vibration and sound radiation control includes principally two layers. The first layer has a low stiffness per unit area which allows motion in the direction perpendicular to its ...
    • Active/passive distributed absorber for vibration and sound radiation control 

      Virginia Tech Intellectual Properties, Inc.; Fuller, Christopher R.; Kondylas, Kathleen (United States Patent and Trademark Office, 2012-05-08)
      Vibration or acoustic sound control is achieved using an elastic layer of thermal or insulation material in which a plurality of discrete masses are distributed throughout. The elastic layer may be installed as a pre-formed ...
    • Adaptive bus voltage positioning for two-stage voltage regulators 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Xu, Ming Gang; Wei, Jia (United States Patent and Trademark Office, 2007-01-09)
      Alteration of voltage input to a voltage regulator output stage from a Vbus regulator stage in a two-stage voltage regulator provides optimal Vbus voltage placement for a wide range of current loads ...
    • Adaptive on-time control for power factor correction stage light load efficiency 

      Virginia Tech Intellectual Properties, Inc.; Lee, Fred C.; Wang, Chung-Hsing Hsuan; Xu, Ming Gang; Li, Qian (United States Patent and Trademark Office, 2014-08-12)
      Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous ...
    • Adaptive personal active noise system 

      Virginia Tech Intellectual Properties, Inc.; Saunders, William; Vaudrey, Michael A. (United States Patent and Trademark Office, 2000-06-20)
      An improved personal noise attenuation system which attenuates both tonal and broadband sound and which includes a spatially adjustable acousto-electric sensor and attenuation means including both feedback and feed forward ...
    • Algorithm and implementation system for measuring impedance in the D-Q domain 

      Virginia Tech Intellectual Properties, Inc.; Mattavelli, Paolo; Karimi, Kamiar J.; Wang, Fred; Burgos, Rolando; Boroyevich, Dushan; Fu, Sheau-Wei (Johnny); Francis, Gerald; Shen, Zhiyu (United States Patent and Trademark Office, 2015-09-22)
      A controller and infrastructure for an impedance analyzer measures responses to perturbations to respective phases of a multi-phase system at an interface between stages thereof (which may be considered as a source and ...
    • Alkali corrosion resistant coatings and ceramic foams having superfine open cell structure and method of processing 

      The Center of Innovative Technology; Virginia Polytechnic Institute and State University; Virginia Tech Intellectual Properties, Inc.; Brown, Jr., Jesse J.; Hirschfeld, Deidre A.; Li, Tingkai (United States Patent and Trademark Office, 1993-12-07)
      Alkali corrosion resistant coatings and ceramic foams having superfine open cell structure are created using sol-gel processes. The processes have particular application in creating calcium magnesium zirconium phosphate, ...
    • Alkylene oxide esters of lignin sulfonic acid 

      Virginia Tech Intellectual Properties, Inc.; Glasser, Wolfgang G.; Dhara, Kaliprasanna (United States Patent and Trademark Office, 1992-04-07)
      Lignin sulfonates are converted into sulfonic acid esters by blocking free phenolic hydroxyl groups on the lignin sulfonates from reaction with a suitable protective group, subjecting the blocked lignin sulfonate in aqueous ...
    • Amine compounds and curable compositions derived therefrom 

      Virginia Tech Intellectual Properties, Inc.; Wilkes, Garth L.; Li, Chenghong (United States Patent and Trademark Office, 2003-01-14)
      Disclosed are compounds produced by a process comprising the step of reacting an amine reactant with an epoxide reactant to form a hydrolytically stable carbon-nitrogen bond therebetween, wherein at least one of the amine ...
    • Amine compounds and curable compositions derived therefrom 

      Virginia Tech Intellectual Properties, Inc.; Wilkes, Garth L.; Li, Chenghong (United States Patent and Trademark Office, 2006-11-07)
      Disclosed are compounds produced by a process comprising the step of reacting an amine reactant with an epoxide reactant to form a hydrolytically stable carbon-nitrogen bond therebetween, wherein at least one of the amine ...