Patents by Inventor Raman Viswanathan
Raman Viswanathan 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).
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Patent number: 10365402Abstract: A method and system for transmitting data through a transmission medium between surface and subsurface transceivers. A surface transceiver and a subsurface transceiver are each configured to selectively transmit over a plurality of transmission channels, each transmission channel having a range of frequencies within the total frequency bandwidth. The surface transceiver is adapted to initialize a channel to determine at least one parameter affecting the current maximum data rate for transmission of information through the channel using a given transmission methodology. At least one of the channels uses carrierless phase/amplitude (CAP) modulation for its transmission methodology. The surface transceiver and the subsurface transceiver adapt to cooperatively periodically test a channel by transmission of a calibration signal from the subsurface transceiver to the surface transceiver.Type: GrantFiled: May 26, 2017Date of Patent: July 30, 2019Assignee: Baker Hughes, a GE Company, LLCInventors: Otto Fanini, Raman Viswanathan, Jorge Maxit, Harold Andrade
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Publication number: 20170261641Abstract: A method and system for transmitting data through a transmission medium between surface and subsurface transceivers. A surface transceiver and a subsurface transceiver are each configured to selectively transmit over a plurality of transmission channels, each transmission channel having a range of frequencies within the total frequency bandwidth. The surface transceiver is adapted to initialize a channel to determine at least one parameter affecting the current maximum data rate for transmission of information through the channel using a given transmission methodology. At least one of the channels uses carrierless phase/amplitude (CAP) modulation for its transmission methodology. The surface transceiver and the subsurface transceiver adapt to cooperatively periodically test a channel by transmission of a calibration signal from the subsurface transceiver to the surface transceiver.Type: ApplicationFiled: May 26, 2017Publication date: September 14, 2017Applicant: Baker Hughes IncorporatedInventors: Otto Fanini, Raman Viswanathan, Jorge Maxit, Harold Andrade
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Patent number: 9664815Abstract: A method and system for transmitting data through a transmission medium in a wellbore. A surface transceiver and a subsurface transceiver are each configured to selectively transmit over a plurality of transmission channels. The surface transceiver is adapted to initialize a channel to determine at least one parameter affecting the current maximum data rate for transmission of information through the channel using a given transmission methodology. At least one of the channels uses carrierless phase/amplitude (CAP) modulation for its transmission methodology. The surface transceiver and the subsurface transceiver adapt to cooperatively periodically test a channel by transmission of a calibration signal from the subsurface transceiver to the surface transceiver. Control circuitry compares the received calibration signal with the calibration signal, responding to the result of the comparison to adjust at least one parameter as necessary to achieve an optimum rate of data transmission through said channel.Type: GrantFiled: September 25, 2008Date of Patent: May 30, 2017Assignee: Baker Hughes IncorporatedInventors: Otto N. Fanini, Raman Viswanathan, Jorge Omar Maxit, Harold Andrade
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Patent number: 9580414Abstract: The present invention relates to a novel salt of (3aR,4S,7R,7aS)-2-[((1R,2R)-2-{[4-(1,2-benzisothiazol-3-yl)-piperazin-1-yl]methyl}cyclohexyl)methyl]hexahydro-1H-4,7-methanisoindol-1,3-dione and hydrates thereof, to methods for preparing the novel salt and its hydrates. In one aspect, the present invention provides a compound which is lurasidone dihydrochloride. In another aspect, the present invention provides a process for preparation of lurasidone dihydrochloride comprising: (i) mixing lurasidone free base in an organic solvent system; (ii) subjecting step (i) mixture to acid proton source; and (iii) isolating compound of lurasidone dihydrochloride.Type: GrantFiled: July 18, 2013Date of Patent: February 28, 2017Assignee: Shasun Pharmaceuticals LimitedInventors: Vijayabaskar Veerappan, Srimurugan Sankareswaran, Sathish Kumar Raman Viswanathan, N. Subramanian
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Publication number: 20150175596Abstract: The present invention relates to a novel salt of (3aR,4S,7R,7aS)-2-[((1R,2R)-2-{[4-(1,2-benzisothiazol-3-yl)-piperazin-1-yl]methyl}cyclohexyl)methyl]hexahydro-1H-4,7-methanisoindol-1,3-dione and hydrates thereof, to methods for preparing the novel salt and its hydrates. In one aspect, the present invention provides a compound which is lurasidone dihydrochloride. In another aspect, the present invention provides a process for preparation of lurasidone dihydrochloride comprising: (i) mixing lurasidone free base in an organic solvent system; (ii) subjecting step (i) mixture to acid proton source; and (iii) isolating compound of lurasidone dihydrochloride.Type: ApplicationFiled: July 18, 2013Publication date: June 25, 2015Inventors: Vijayabaskar Veerappan, Srimurugan Sankareswaran, Sathish Kumar Raman Viswanathan, N. Subramanian
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Patent number: 8581742Abstract: A suspended well logging device for use in a wellbore drilled in an earthen formation may include a cable configured to be conveyed into the wellbore; a single twisted pair of conductors positioned in the cable; and a conductive armor surrounding the single twisted pair of conductors. In embodiments, the device may further include a first channel formed using the single twisted pair of conductors; a second channel formed using the single twisted pair of conductors and the armor; and a wellbore logging tool coupled to an end of the cable.Type: GrantFiled: April 16, 2008Date of Patent: November 12, 2013Assignee: Baker Hughes IncorporatedInventors: Raman Viswanathan, Randy Gold
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Patent number: 8023690Abstract: The disclosure, in one aspect, provides a method for providing an image of a fluid that includes passing light through the fluid, detecting light passing through the fluid at at least one wavelength and producing signals corresponding to the detected light, and processing the signals to provide the image of the fluid.Type: GrantFiled: January 31, 2007Date of Patent: September 20, 2011Assignee: Baker Hughes IncorporatedInventors: Rocco DiFoggio, Raman Viswanathan, Jeffery W. Fontenot
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Publication number: 20100295702Abstract: A Full-Duplex Pre-equalized OFDM system for high speed telemetry down-hole wire-line communication. The system compensates for the narrow bandwidth, high attenuation of, and noise in a downhole wireline using Trellis Code Modulation and Reed Solomon encoding.Type: ApplicationFiled: May 17, 2010Publication date: November 25, 2010Applicant: Baker Hughes IncorporatedInventors: Jinsong Zhao, Harold Andrade, Jorge O. Maxit, Raman Viswanathan
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Publication number: 20100073190Abstract: A method and system for transmitting data through a transmission medium between surface and subsurface transceivers. A surface transceiver and a subsurface transceiver are each configured to selectively transmit over a plurality of transmission channels, each transmission channel having a range of frequencies within the total frequency bandwidth. The surface transceiver is adapted to initialize a channel to determine at least one parameter affecting the current maximum data rate for transmission of information through the channel using a given transmission methodology. At least one of the channels uses carrierless phase/amplitude (CAP) modulation for its transmission methodology. The surface transceiver and the subsurface transceiver adapt to cooperatively periodically test a channel by transmission of a calibration signal from the subsurface transceiver to the surface transceiver.Type: ApplicationFiled: September 25, 2008Publication date: March 25, 2010Applicant: Baker Hughes IncorporatedInventors: Otto N. Fanini, Raman Viswanathan, Jorge Omar Maxit, Harold Andrade
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Publication number: 20080218375Abstract: A suspended well logging device for use in a wellbore drilled in an earthen formation may include a cable configured to be conveyed into the wellbore; a single twisted pair of conductors positioned in the cable; and a conductive armor surrounding the single twisted pair of conductors. In embodiments, the device may further include a first channel formed using the single twisted pair of conductors; a second channel formed using the single twisted pair of conductors and the armor; and a wellbore logging tool coupled to an end of the cable.Type: ApplicationFiled: April 16, 2008Publication date: September 11, 2008Applicant: Baker Hughes IncorporatedInventors: Raman VISWANATHAN, Randy GOLD
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Patent number: 7399573Abstract: The negative resist compositions especially suitable for electron beam-based lithographic processes are obtained by using a polymeric component containing first silsesquioxane moieties functionalized with a first reactive group having a first crosslinking reactivity and a first dissolution rate in aqueous alkaline solutions, and second silsesquioxane moieties functionalized with a second reactive group having a second crosslinking reactivity and a second dissolution rate in aqueous alkaline solutions, said reactivities being different from one another and said dissolution rates being different from one another. These negative resists enable improved negative lithographic processes, especially in the context of mask-making and direct-write techniques using electron beam lithography. The negative resists are also useful more generally in methods of forming patterned material features and advantageously show reduced incidence of image collapse at smaller groundrules.Type: GrantFiled: October 25, 2006Date of Patent: July 15, 2008Assignee: International Business Machines CorporationInventors: Wu-Song S. Huang, Lidija Sekaric, James J. Bucchignano, David P. Klaus, Raman Viswanathan
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Publication number: 20080102400Abstract: The negative resist compositions especially suitable for electron beam-based lithographic processes are obtained by using a polymeric component containing first silsesquioxane moieties functionalized with a first reactive group having a first crosslinking reactivity and a first dissolution rate in aqueous alkaline solutions, and second silsesquioxane moieties functionalized with a second reactive group having a second crosslinking reactivity and a second dissolution rate in aqueous alkaline solutions, said reactivities being different from one another and said dissolution rates being different from one another. These negative resists enable improved negative lithographic processes, especially in the context of mask-making and direct-write techniques using electron beam lithography. The negative resists are also useful more generally in methods of forming patterned material features and advantageously show reduced incidence of image collapse at smaller groundrules.Type: ApplicationFiled: October 25, 2006Publication date: May 1, 2008Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventors: Wu-Song S. Huang, Lidija Sekaric, James J. Bucchignano, David P. Klaus, Raman Viswanathan
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Publication number: 20070212654Abstract: A method of lithography is disclosed, which allows for independent resist process optimization of two or more exposure steps that are performed on a single resist layer. By providing for a separate post-exposure bake after each resist exposure step, pattern resolution for each exposure can be optimized. The method can generally be used with different lithographic techniques, and is well-suited for hybrid lithography. It has been applied to the fabrication of a device, in which the active area and the gate levels are defined in separate mask levels using hybrid lithography with an e-beam source and a 248 nm source respectively. Conditions for post-exposure bakes after the two exposure steps are independently adjusted to provide for optimized results.Type: ApplicationFiled: March 9, 2006Publication date: September 13, 2007Applicant: International Business Machines CorporationInventors: Carl Larson, Sharee McNab, Steven Steen, Raman Viswanathan, Gregory Wallraff
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Publication number: 20070188346Abstract: A suspended well logging apparatus is provided having downhole well data acquired by a sensor, transmitted to the surface via complementary modems, and conveyed to the surface modem via a data transmission cable linking the modems, the cable having at least one twisted pair of signal conductors positioned within an outer protective sheath, each of the conductors being separately insulated, the at least one twisted pair of signal conductors having a twist rate of at least ? twist per inch, an insulation sheath surrounding the twisted pair of conductors and a tensile load carrier surrounding the insulation sheath, the load carrier comprising a sheath of tensile load carrying filaments enabling self support of the well logging cable.Type: ApplicationFiled: December 15, 2006Publication date: August 16, 2007Applicant: Baker Hughes IncorporatedInventors: Raman Viswanathan, Randy Gold
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Publication number: 20070120051Abstract: The disclosure, in one aspect, provides a method for providing an image of a fluid that includes passing light through the fluid, detecting light passing through the fluid at least one wavelength and producing signals corresponding to the detected light, and processing the signals to provide the image of the fluid.Type: ApplicationFiled: January 31, 2007Publication date: May 31, 2007Applicant: BAKER HUGHES INCORPORATEDInventors: Rocco DiFoggio, Raman Viswanathan, Jeffery Fontenot
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Publication number: 20060275694Abstract: Non-chemically amplified radiation sensitive resist compositions containing silicon are especially useful for lithographic applications, especially E-beam lithography. More particularly, radiation-sensitive resist compositions comprising a polymer having at least one silicon-containing moiety and at least one radiation-sensitive moiety cleavable upon radiation exposure to form aqueous base soluble moiety can be used to pattern sub-50 nm features with little or no blur.Type: ApplicationFiled: June 7, 2005Publication date: December 7, 2006Applicant: International Business Machines CorporationInventors: James Bucchignano, Wu-Song Huang, David Klaus, Lidija Sekaric, Raman Viswanathan
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Publication number: 20050219063Abstract: A suspended well logging apparatus is provided having downhole well data acquired by a sensor, transmitted to the surface via complementary modems, and conveyed to the surface modem via a data transmission cable linking the modems, the cable having at least one twisted pair of signal conductors positioned within an outer protective sheath, each of the conductors being separately insulated, the at least one twisted pair of signal conductors having a twist rate of at least ? twist per inch, an insulation sheath surrounding the twisted pair of conductors and a tensile load carrier surrounding the insulation sheath, the load carrier comprising a sheath of tensile load carrying filaments enabling self support of the well logging cable.Type: ApplicationFiled: March 22, 2005Publication date: October 6, 2005Applicant: Baker Hughes IncorporatedInventors: Raman Viswanathan, Randy Gold
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Publication number: 20030011489Abstract: A communication protocol based upon the Asymmetric Digital Subscriber Line (ADSL) protocol developed for telephone communications is used for two way transmission of data between a downhole logging device and a surface device. The total available bandwidth for a pair of conductors is determined by the length of the conductors and the choice of conductors (operational mode) of a conventional 7 conductor wireline. The available bandwidth is partitioned into channels with a bandwidth of 4.3125 kHz, each of the channels carrying a portion of the data. A contiguous subset of the channels is used for downward communication and another subset is used for upward communication. The bit loading is dynamically determined based upon monitoring of the noise level. Optionally, more than one mode of the 7 conductor wireline may be used.Type: ApplicationFiled: June 14, 2002Publication date: January 16, 2003Applicant: Baker Hughes, Inc.Inventor: Raman Viswanathan
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Patent number: 4556884Abstract: An improved well logging technique is provided for more accurately deriving and correlating a plurality of measurements made during a single traversal of a logging instrument through subsurface formations. In one exemplary embodiment, methods and apparatus are provided for deriving a more accurate and precise measurement of depth at which real-time logging measurements are made, and in particular for correcting anomalies occurring in the depth indication from cable stretch, yo-yo of the sonde in the borehole and the like. The more accurate and precise depth measurement is then utilized for generating well logging measurements on a depth-dependent basis, deriving at least some of such measurements in digital form and alternately transmitting to the surface digital and analog representations of such measurements.Type: GrantFiled: March 26, 1982Date of Patent: December 3, 1985Assignee: Dresser Industries, Inc.Inventors: Anthony P. S. Howells, Anthony M. Dienglewicz, Raman Viswanathan, Jorg A. Angehrn
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Patent number: 4346593Abstract: Improved methods and apparatus are provided for correlatively matching, recording, and displaying, two or more sets of logging data measurements with respect to the borehold depth at which they were generated, and independent of their historical or real-time character. In a particular embodiment of the invention, measurements from each set of data derived or sampled at correlative depths are adjacently displayed in graphical form during a logging operation. The depth offset between the measurements is visually or automatically detected, and in response thereto, the subsequent correlation of other selected measurements and depths at which subsequent measurements are derived are thereby adjusted for further processing, display and recording.Type: GrantFiled: October 9, 1980Date of Patent: August 31, 1982Assignee: Dresser Industries, Inc.Inventors: Anthony P. S. Howells, Raman Viswanathan, Jorg A. Angehrn