Patents by Inventor David E. Ferguson
David E. Ferguson 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: 7137306Abstract: Apparatus and an accompanying method for use in a conventional dynamic material testing system to advantageously provide enhanced self-resistive specimen heating. Specifically, a fixture (400) is added to the system. The fixture has two supporting arms (201, 451), each holding one of two opposing and conductive anvil assemblies (200, 453). The fixture applies adequate force to each arm sufficient to hold a specimen (466) in position between the anvil assemblies and establish a good abutting electrical contact between the specimen and each assembly but without exerting enough force to deform the specimen as it is being heated. Separate opposing and existing coaxially-oriented shafts (406, 408) controllably strike both arms and move the anvils together, hence squeezing the specimen and generating each deformation therein.Type: GrantFiled: June 25, 2004Date of Patent: November 21, 2006Assignee: Dynamic Systems Inc.Inventors: David E. Ferguson, Norman A. Lindeman
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Patent number: 7107857Abstract: Apparatus for use in a conventional dynamic material testing system to advantageously provide uniform self-resistive specimen heating with enhanced temperature uniformity. Specifically, an anvil stack (300) in an anvil assembly (200) has a foil interface (242) with a composite layer (320A, 320B, 320C) containing, e.g., a concentrically oriented multi-component arrangement formed of an inner high strength and insulating disk (315, 325, 335) and an outer ring-shaped resistive region (313, 323, 333), situated between an anvil base (241) and an anvil top (240). An insulating member (243) electrically and thermally insulates all sides of the anvil stack from its supporting structure.Type: GrantFiled: June 25, 2004Date of Patent: September 19, 2006Assignee: Dynamic Systems Inc.Inventors: David E. Ferguson, Norman A. Lindeman
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Patent number: 5751623Abstract: A method and apparatus for efficiently adding and subtracting multiple digit decimal numbers represented as a series of 8-bit bytes, each 8-bit byte representing one digit of a decimal number. In accordance with the present invention, numeric values are stored internally within a computer in a new format, referred to as "X7B". Numeric input into the computer can be in any form, such as binary, ASCII, EBCDIC, X7B, etc. X7B values are computed by adding the 8-bit binary representation of each decimal digit to a binary value of"0111 1011" (i.e., "7B" hexadecimal).Type: GrantFiled: November 22, 1995Date of Patent: May 12, 1998Assignee: Amalgamated Software of North America, Inc.Inventor: David E. Ferguson
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Patent number: 5664184Abstract: A method and apparatus for increasing the speed of a search through leaf nodes of an inventive key index tree structure, known as a "Q-tree". The present invention identifies "decision-bits" within leaf node entries and uses these decision-bits to accelerate searches for a particular record or for a record adjacent to which a new record is to be inserted. A decision-bit is a particular type of distinction-bit having the smallest value and associated with a search key a greater value then the keys associated with other distinction-bits of the same value within a specified search range. Each decision-bit divides a search range into "left" and "right" parts. One of the two parts will constitute a "new" search range. A "quit-bit" having an ordinal number equal to the value of the decision-bit for the search range, is tested. If the quit-bit is "on", then the right, or greater value, part becomes the new search range. Otherwise, the left, or lesser value, part becomes the new search range.Type: GrantFiled: November 29, 1995Date of Patent: September 2, 1997Assignee: Amalgamated Software of North America, Inc.Inventors: David E. Ferguson, Eduardo C. Ross
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Patent number: 5587940Abstract: A method and apparatus for performing decimal division using a computer that does not have the capability to perform single instruction decimal multiplication or division. A divisor is normalized such that the value of the first digit of the divisor is not less than 5. Trial quotient digits within a trial quotient table are predetermined. A multiples table comprises multiples of the normalized divisor. The most significant digits of the normalized divisor and the most significant digits of each partial dividend are used to locate trial quotient digits within the trial quotient digit table. The trial quotient digits are used to locate multiples within the multiples table. A single subtraction (or addition) operation from a partial dividend can be used to determine whether the trial quotient digit is the actual quotient digit.Type: GrantFiled: November 12, 1993Date of Patent: December 24, 1996Assignee: Amalgamated Software of North America, Inc.Inventor: David E. Ferguson
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Patent number: 5497485Abstract: A method and apparatus for increasing the speed of a search through leaf nodes of an inventive key index tree structure, known as a "Q-tree". The present invention identifies "decision-bits" within leaf node entries and uses these decision-bits to accelerate searches for a particular record or for a record adjacent to which a new record is to be inserted. A decision-bit is a particular type of distinction-bit having the smallest value and associated with a search key a greater value then the keys associated with other distinction-bits of the same value within a specified search range. Each decision-bit divides a search range into "left" and "right" parts. One of the two parts will constitute a "new" search range. A "quit-bit" having an ordinal number equal to the value of the decision-bit for the search range, is tested. If the quit-bit is "on", then the right, or greater value, part becomes the new search range. Otherwise, the left, or lesser value, part becomes the new search range.Type: GrantFiled: May 21, 1993Date of Patent: March 5, 1996Assignee: Amalgamated Software of North America, Inc.Inventors: David E. Ferguson, Eduardo C. Ross
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Patent number: 5274805Abstract: A method for sorting data in a computer data storage system that has particular advantages in implementing a key index tree structure. The sorting method uses buffer-size substrings to sort strings of key records into a linked list structure that can be directly transformed into an index tree. The sorting method also may be used for sorting large sets of data records in place on a computer storage system. The method further integrates prefix compression and suffix compression of key records with the sorting method to reduce the number of input/output operations required to create a more compact key index tree structure.Type: GrantFiled: June 5, 1992Date of Patent: December 28, 1993Assignee: Amalgamated Software of North America, Inc.Inventors: David E. Ferguson, Eduardo C. Ross
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Patent number: 5121493Abstract: A method for sorting data in a computer data storage system that has particular advantages in implementing a key index tree structure. The sorting method uses buffer-size substrings to sort strings of key records into a linked list structure that can be directly transformed into an index tree. The sorting method also may be used for sorting large sets of data records in place on a computer storage system.Type: GrantFiled: January 19, 1990Date of Patent: June 9, 1992Assignee: Amalgamated Software of North America, Inc.Inventor: David E. Ferguson
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Patent number: 4677550Abstract: An improved method for indexing and accessing data stored in a computer storage system, comprising a multi-way tree structure having interconnected branch nodes and leaf nodes. The leaf nodes contain a large number of distinction bits, rather than a smaller number of search keys as known in the prior art. A distinction bit is determined by comparing two selected search keys and determining the ordinal number of the first bit that is different between the two keys. The density of distinction bit entries in the leaf nodes permits shorter access times to obtain data records in a computer storage system.Type: GrantFiled: September 30, 1983Date of Patent: June 30, 1987Assignee: Amalgamated Software of North America, Inc.Inventor: David E. Ferguson