Virginia Tech Patents
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These United States Patents were originally assigned to Virginia Tech.
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- 2-aroyl-4-acyl paclitaxel (Taxol) analogs(United States Patent and Trademark Office, 2002-11-05)2-debenzoyl-4-deacetyl paclitaxel, antineoplastic analogs thereof and intermediates are taught, as well as the formation of the compound, analogs and intermediates. The compound, analogs and intermediates may be used to form pharmaceutical compositions having anti-neoplastic activity. Further, the compound, analogs and intermediates may be used to treat cancer when applied in an effective amount by means such as a pharmaceutical composition.
- 2-debenzoyl-2-acyl taxol derivatives and method for making same(United States Patent and Trademark Office, 1999-12-14)The present invention relates to 2-debenzoyl-2-acyl taxol derivatives, analogues thereof and methods for making same. Compounds of the present invention include compounds having the general formula: ##STR1## wherein R.sub.1 is an alkyl or substituted alkyl; R.sub.2 is selected from the group consisting of H and C(O)R.sub.a ; R.sub.3 is selected from the group consisting of H, protecting groups, R.sub.b, and C(O)R.sub.b ; R.sub.4 is selected from the group consisting of H and C(O)R.sub.c, and wherein R.sub.a, R.sub.b, and R.sub.c are independently selected from the group consisting of alkyls, substituted alkyls, alkenyls, alkynyls, aryls, and substituted aryls; provided that R.sub.a is other than phenyl and 3-hydroxyphenyl.
- 2-Debenzoyl-2-acyl taxol derivatives and methods for making same(United States Patent and Trademark Office, 1997-12-30)Compounds having the general formula: ##STR1## wherein R.sub.1 is an alkyl or substituted alkyl; R.sub.2 is selected from the group consisting of H and C(O)R.sub.a ; R.sub.3 is selected from the group consisting of H, protecting groups, R.sub.b, and C(O)R.sub.b ; R.sub.4 is selected from the group consisting of H and C(O)R.sub.c, and wherein R.sub.a, R.sub.b, and R.sub.c are independently selected from the group consisting of alkyls, substituted alkyls, alkenyls, alkynyls, aryls, and substituted aryls; provided that R.sub.a is other than phenyl and 3-hydroxyphenyl.
- 2T-1C ferroelectric random access memory and operation method thereof(United States Patent and Trademark Office, 2002-06-11)A 2T-1C FRAM, each cell of which includes two transistors and one ferroelectric capacitor so that the “charging” and “discharging” of the ferroelectric capacitor used in conjunction with the p-n junction of the two transistors performs write/read operations without switching thereby avoiding degradation problems such as fatigue and imprint in the 2T-1C FRAM.
- 3D printing part removal and interface for a 3D printing vending machine(United States Patent and Trademark Office, 2018-04-03)The present invention concerns a system and method for fabricating a three-dimensional object. A build platform is provided that defines a build area and includes a print bed within the build area. Also provided is an extruder that extrudes build material. An ejector having at least one arm that has at least two opposing ends is used to remove the printed object. The first end of the ejector is adapted to travel in a vertical direction and the second end is adapted to travel in a horizontal direction. A scraper portion extends horizontally, parallel to the print bed from a retracted position to an extended position when the first end travels in a vertical direction towards the print bed.
- 3D printing vending machine(United States Patent and Trademark Office, 2016-08-16)A vending machine for creating a three-dimensional object having an enclosure having an exterior and interior. The interior receives and houses at least one three-dimensional printer. An interface for accepting an instruction associated with an object to be printed and transmitting the instruction to the printer. A storage section for storing a printed object that provides access to the printed part but limits or prohibits access to the interior.
- 7-deoxy-6-substituted paclitaxels(United States Patent and Trademark Office, 1998-06-30)The present invention concerns novel paclitaxel derivatives, their use as antitumor agents, and pharmaceutical formulations.
- Accelerated commutation for passive clamp isolated boost converters(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 circuit, transformer and secondary circuit. The primary circuit takes the form of a “full bridge converter,” a “push-pull converter,” or an “L-type converter.”. The primary circuit may include a dissipator such as a snubber circuit or small buck converter. A secondary side of the transformer is momentarily shorted by the secondary circuit by, for example, turning on at least two switches in the secondary circuit simultaneously for a minimal calibratable period when a pair of primary circuit controllers turn off to protect the primary circuit switches from voltage spikes during switching conditions.
- Accessible kiosk(United States Patent and Trademark Office, 1999-06-01)
- Accurate magnetic field sensor and method for wireless phasor measurement unit(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 generating a transducer output signal representative of the electrical characteristic; an amplifier receiving the transducer output signal and generating an amplifier output signal; a filter receiving the amplifier output signal, low pass filtering the amplifier output signal, and generating a filter output signal; an analog to digital converter receiving the filter output signal and generating a digital output signal; and a processor receiving the digital output signal, calculating phasor data from the digital output signal and generating a data output signal, wherein the calculated phasor data is at least as accurate as phasor data from a phasor measurement unit or a frequency data recorder having a transducer for nontransduction measurement of the same electrical characteristic.
- Acousto-fluidic driver for active control of turbofan engine noise(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 an impedance matching horn in destructively interfering relation with the original noise. Depending on the acoustic noise source and its spatial distribution, the acousto-fluidic amplifier may be a single stage amplifier or multiple stages connected in parallel and/or cascade, with output horns spatially distributed to have the maximum cancellation effect. Sensed noise, prior to fluidic amplification, may be processed in a manner to effect feedback or feedforward control of the amplified acoustic output signals.
- Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors(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 channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.
- Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors(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 channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.
- Active dual reaction mass absorber for vibration control(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 with respect to said frame. The absorber includes a force generating member for controlling relative movement between the reaction mass elements for damping vibration of the structure. The inventive dual reactive mass absorber requires less control force to produce the same vibration attenuation as conventional single reactive mass absorbers.
- Active/passive distributed absorber for vibration and sound radiation control(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 main plane. The second layer is principally a mass layer. These two combined layers have a frequency of resonance close to one of the main structure. The dynamic behavior of the coupled system makes the active/passive absorber a passive absorber; however, the first layer can be electrically actuated to induce motion in the direction perpendicular to its main plane. This addition property induces and/or changes the motion of the mass layer and therefore improves the dynamic properties of the active/passive absorber system. The active/passive absorber can have multiple mass layers and multiple elastic layers stacked one on top of the other. In addition, the mass layers can be continuous or discretized, and have varying thicknesses and shapes for sections and/or segments in the mass layer.
- Active/passive distributed absorber for vibration and sound radiation control(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 layer, or be blown into position within a structure where vibration or acoustic sound control is required.
- Active/passive distributed absorber for vibration and sound radiation control(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 layer, or be blown into position within a structure where vibration or acoustic sound control is required.
- Active/passive distributed absorber for vibration and sound radiation control(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 main plane. The second layer is principally a mass layer. These two combined layers have a frequency of resonance close to one of the main structure. The dynamic behavior of the coupled system makes the active/passive absorber a passive absorber; however, the first layer can be electrically actuated to induce motion in the direction perpendicular to its main plane. This addition property induces and/or changes the motion of the mass layer and therefore improves the dynamic properties of the active/passive absorber system. The acive/passive absorber can have multiple mass layers and multiple elastic layers stacked one on top of the other. In addition, the mass layers can be continuous or discretized, and have varying thicknesses and shapes for sections and/or segments in the mass layer.
- Active/passive distributed absorber for vibration and sound radiation control(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 main plane. The second layer is principally a mass layer. These two combined layers have a frequency of resonance close to one of the main structure. The dynamic behavior of the coupled system makes the active/passive absorber a passive absorbe; however, the first layer can be electrically actuated to induce motion in the direction perpendicular to its main plane. This addition property induces and/or changes the motion of the mass layer and therefore improves the dynamic properties of the active/passive absorber system.
- Adaptive bus voltage positioning for two-stage voltage regulators(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 to increase voltage regulator efficiency and is particularly suited to CPUs having power-saving sleep modes of operation. An optimal voltage is selected or developed in response to information concerning operational mode or current consumption of the powered device. As a perfecting feature of one embodiment of the invention in which a discrete Vbus voltage is selected based on operational mode, the selected voltage is adjusted to further optimize the matching of the Vbus voltage placement to the load and provides a continuous range of voltages. In a second embodiment the entire Vbus positioning function is performed in response to current load information. A feed-forward arrangement is provided to avoid transient spikes as the Vbus voltage placement is altered.