Abstract: A media stackloader processes removable data storage media such as optical disks, magnetic diskettes, or tape media. The stackloader removably couples to a storage drive, such as by plugging into a slot of the host computer. The stackloader has a plug portion integral with a housing portion, the plug portion plugging into the host computer and the housing portion housing a magazine containing the removable media. The stackloader includes a device for moving the magazine vertically within the housing to align selected cartridges with an opening in one of the drives of the personal computer. After the cartridge is aligned, a device is employed for moving the cartridge horizontally into the drive for processing and, after processing, for withdrawing the cartridge from the drive back into the magazine. A locking mechanism selectively locks and unlocks the cartridges to prevent improper removal of cartridges from the magazine.
Type:
Grant
Filed:
December 22, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Chi-Hung Dang, Kamal Emile Dimitri, John Edward Kulakowski, Rodney Jerome Means
Abstract: A method, apparatus and article for manufacture for generating static, dynamic and hybrid sparse indices for use with workfiles used by SQL queries in a relational database management system. A workfile and a sparse index structure are temporarily created in the computer during execution of the query by the computer. The workfile stores intermediate relations resulting from execution of a portion of the SQL query, wherein the intermediate relations comprise sorted rows for an inner table referenced in the SQL query. The sparse index structure contains one or more entries indicating at least an approximate location for at least some of the rows in the workfile. As one or more rows from an outer table referenced in the SQL query are retrieved, the entries of the sparse index structure are searched for a closest matching entry for each retrieved row. The sorted workfile is then scanned for a row matching each retrieved row using the closest matching entry from the sparse index structure as a starting position.
Type:
Grant
Filed:
February 24, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Gautam Bhargava, Paramesh Sampatrai Desai, Piyush Goel, Peter Hoa, Fen-Ling Lin, Balakrishna Raghavendra Iyer, Jerry Mukai, William Samuel Perlman, Hong Sang Tie
Abstract: A coil encircling the ferrite core of a magnetic head attached to a slider used in a hard disk drive is formed using two mating chips. A first chip having layered wires and bonding bumps is inserted in the winding window between the ferrite core and the body of the slider. A second chip having layered wires, bonding bumps and a groove straddling the ferrite core is disposed outside the winding window and mates with the first chip. Bonding bumps, comprising low-melting solder, are heat bonded to form a continuous coil.
Type:
Grant
Filed:
September 6, 1996
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: Packaged signal routing circuits (e.g. on printed circuit cards or boards), route pulse signals with very short rise times from a lossy driver to multiple devices. In these routing circuits, a complex network of conductors branches from a common junction adjacent the driver output into multiple conduction paths of unequal length. In accordance with the invention, the internal impedance of the driver is matched to the aggregate characteristic impedance of the branch paths, and a lossless compensating circuit is attached to a shortest branch path. The compensating circuit is designed to transfer signal reflections of predetermined form to the branching junction at the driver via the shortest branch.
Abstract: Described herein is a system and method for operating a data processing system having a processing unit and physical storage in which data is stored. The storage is connected to the processing unit for transferring pages of data to the processing unit. The storage contains at least one database table stored on a plurality of pages. Each data base table has a plurality of rows of data, and one or more indexes composed of a sequence of entries which reference the rows. The processing unit has a memory associated with it. A portion of the memory comprises a buffer pool for caching data pages from the table. The method operates by scanning one or more selected indexes in determining the relationship of the number of data transfers required to traverse all or a portion of each selected index for a selected range of buffer pool sizes. Then, a description of this relationship is stored.
Type:
Grant
Filed:
May 12, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Bernhard Schiefer, Arun Narasimha Swami
Abstract: An application request for off-screen VRAM is satisfied transparently to the application by allocating off-screen VRAM, if available, or system RAM if off-screen VRAM is unavailable. In addition, a list is kept of previous memory requests so that requests which were satisfied by allocating system RAM can be switched to off-screen VRAM, if such off-screen VRAM should later become available. Allocation of off-screen VRAM is controlled by a device driver that responds to various application memory requests and controls the off-screen VRAM resources, among other things. The device driver receives an allocation request for off-screen VRAM and determines whether the request may be honored with available off-screen VRAM resources. If the request can be honored with available off-screen VRAM resources, the device driver allocates a portion of the available off-screen VRAM resources to honor the request and decreases the amount of available off-screen VRAM resources.
Type:
Grant
Filed:
August 11, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Joseph Celi, Jr., John P. Coffey, Jonathan Mark Wagner
Abstract: A gain cell in a memory array having read and write bitlines and wordlines, wherein the gain cell comprises a write transistor, a storage node, a read transistor, and a diode is disclosed. The write transistor allows the value of the write bitline to be stored onto the storage node when activated by the write wordline. The read transistor, which allows the stored value to be read, is coupled to the storage node and to the read bitline via the diode. The diode prevents the conduction of the read transistor in the opposite direction, thus preventing read interference from other cells and reducing bitline capacitance.
Type:
Grant
Filed:
February 19, 1997
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Russell J. Houghton, Claude L. Bertin, John A. Fifield, Christopher P. Miller, William R. Tonti
Abstract: An efficient method and system of communicating and accumulating global information for parallel data mining. Since each database is partitioned, a single node in a parallel environment will be unable to make decisions based on global information. A novel technique of progressive thresholding is devised to accumulates global information as a function of a transaction support threshold while minimizing transmission overhead. The transaction support threshold is varied as a function of the number of nodes contributing to the global information progresses.
Type:
Grant
Filed:
June 28, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: A method and program for use with a massively parallel processor (MPP) system or a distributed computer system for providing a physical design layout database across several nodes of the system. A user inputs a first datafile representing the physical configuration of the distributed processor system, and inputs a second datafile representing application tablespaces and/or database system files to be stored in the distributed processor system. The program optionally assigns the tablespaces in the second datafile to the physical configuration of the distributed processor system as specified in the first datafile and per the number of nodes, number of disks per node, and the size of the disks. The user may optionally use the physical design layout of the program, may change a portion of the intermediate physical design layout, or may provide the entire physical database design layout, as desired.
Type:
Grant
Filed:
November 8, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: An improved particle lens has an axis that is shifted to follow the central ray of the beam as it is deflected through the lens creating, in effect, a variable curvilinear optical axis for the lens and introducing aberrations having depending on the object size and the distance off the lens symmetry axis. These aberrations are corrected by a set of correction elements generating compensating aberrations of the same type, comprising at least one wire pair perpendicular to the system axis and carrying fixed currents to introduce a gradient in the field, together with three coils centered on the system axis to cancel a bias field introduced by the wire pair.
Type:
Grant
Filed:
December 18, 1996
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: An efficient method for adding one or more new direct access storage devices (DASDs) to a redundant array of independent disks (RAID) array without disrupting ongoing operation of the array. In one embodiment, after contents of new DASDs are initialized off-line, the "parity" or "data" status of specific storage locations in the array is re-mapped, without any changes to the storage locations' contents. In a second embodiment, RAID arrays are efficiently expanded and parallelism is facilitated for original as well as new data by re-mapping parity and data tracks, changing the contents of a minimum number of tracks and maintaining the contents of others.
Type:
Grant
Filed:
December 8, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
David Mun-Hien Choy, Jaishankar Moothedath Menon
Abstract: A system and method of using spare disk bandwidth and buffer capacity maximizes the system throughput of a multimedia server. An important issue is determining a criterion for selecting a data stream for which the additional disk bandwidth should be used. Minimization of buffer consumption is selected as the criterion to select an appropriate media stream to use the spare system resources. Buffer consumption measures not only the amount of buffer but also the amount of time the space is occupied (i.e., the space-time product). Even though both currently active streams and waiting streams can be chosen to adjust the rate of retrieval, it is generally more effective for the active streams.
Type:
Grant
Filed:
July 19, 1995
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: A method of fabricating a high resolution ablation mask for use at laser fluences of greater than 200 mJ/cm.sup.2 is disclosed. The method comprises combining dry etching and chemical etching of an unetched ablation mask which comprises a transparent substrate, a layer of high UV light refractivity material, e.g. aluminum, deposited on said substrate, and a photoresist layer positioned on a predetermined area of said high UV light refractivity material layer leaving other areas of said high UV light refractivity material layer exposed.
Type:
Grant
Filed:
January 29, 1997
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Steven A. Cordes, James L. Speidell, Rajesh S. Patel
Abstract: X-ray lithography is used in the fabrication of very large scale integrated circuits. Optical lithography techniques are used to create a preliminary mask with coarse features in the preparation of a high resolution x-ray mask. The E-beam tool may register the location of the E-beam relative to the optically written coarse features. This helps the tool to navigate according to the location of specific features.
Type:
Grant
Filed:
June 14, 1996
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: A unique event may be generated for a particular part at a particular time that is synchronized with an arbitrary event raised by an arbitrary part for a multimedia title using an interface tool. The particular part of the arbitrary event is visually specified and a time event specifier is placed on the particular part at the particular time in order to generate the unique event. The unique event is displayed as a graphical representation which may be directly manipulated by the developer. In addition, the event specifier may initiate the unique event at a predetermined recurring interval.
Type:
Grant
Filed:
March 29, 1996
Date of Patent:
May 26, 1998
Assignee:
International Business Machine Corp.
Inventors:
John Junior Boezeman, Scott Michael Consolatti, Dennis Donald King
Abstract: In a magnetic read/write assembly, a removable fusible-link shorts the magnetoresistive (MR) sensor element to minimize electrical current through the MR sensing element during discharge of static electricity. Other magnetic head assembly elements such as the write coil and MR magnetic shields are also shorted using fusible-links. The fusible-link is removable during the assembly process. The existing terminal pads and wires are used to remove the fusible-link.
Type:
Grant
Filed:
April 3, 1997
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Inventors:
Peter Beverley Phipps, Erhard Theodor Schreck, Albert John Wallash
Abstract: A match bus operation circuit is disclosed for detecting load/store conflicts created by out-of-order instruction execution in a superscalar microprocessor having first and second busses. A ratio logic compare circuit generates a match bus indicating a match or conflict between the first and second busses. A ratio logic priority circuit is coupled to the ratio logic compare circuit for receiving the match bus and generating a priority bus indicating a first match of the match bus. A ratio logic mask circuit is also coupled to the ratio logic compare circuit for receiving the match bus and generating a mask bus that flags all instructions after the first match for discarding. A ratio logic multiple hit circuit is also coupled to the ratio logic compare circuit and indicates whether more than one instruction has matched.
Type:
Grant
Filed:
February 21, 1997
Date of Patent:
May 26, 1998
Assignee:
International Business Machines Corporation
Abstract: In a data processing system, a first system processor is coupled to a first system bus. The first system processor includes a first bus controller. A second system processor having a second bus controller is coupled to a second system bus. The first bus controller is then coupled to a management bus, and the second bus controller is coupled to the same management bus. Thereafter, at least one feature device is coupled to the first system bus, the second system bus, and the management bus. The feature device is also configured to communicate system processor communications with the first system processor via the first system bus. Next, a problem that affects system processor communications over the first system bus between the feature device and the first system processor is detected. In response to detecting such a communications problem, a command is sent to the feature device via the management bus.
Type:
Grant
Filed:
January 30, 1996
Date of Patent:
May 19, 1998
Assignee:
International Business Machines Corporation
Inventors:
Harry Cheselka, Steven Wade Hunter, Charles Steven Lingafelt, James Gregory Mulkey, John Wagner Yarbrough
Abstract: Apparatus and methods for improved thermal proximity imaging are provided. A data storage medium surface is moved relative to a sensor, in one embodiment a magnetoresistive read/write element. Topographical variations on the storage medium induce temperature changes in the sensor. These temperature changes are monitored to detect the location and nature (e.g., height) of the topographical variations on the medium surface. A feedback circuit using an impedance bridge is disclosed for sensing instantaneous changes in the temperature of the sensor, correcting for the changes and, therefore, keeping the temperature of the sensor substantially constant. By keeping the temperature of the sensor constant, the topographical variations can be detected without any adverse impacts of the surrounding thermal environment on the detection response time.
Type:
Grant
Filed:
November 21, 1996
Date of Patent:
May 19, 1998
Assignee:
International Business Machines Corporation
Inventors:
David William Abraham, Timothy Joseph Chainer, Ferdinand Hendriks