Abstract: A computer system updates a data object that is maintained in data storage external to a database management system (DBMS), after receiving an update request from a DBMS client for the data object, by first scheduling the update request with the DBMS to provide access to the external data object, then initiating a subtransaction in the DBMS for the update request, updating the data object with an in-place update action at the external data storage to thereby produce an updated data object and also updating the DBMS metadata of the data object, next appending information relating to type and time of the update action in an object version table, and then executing a backup operation of the updated data object. This permits update-in-place operations on the external data object, under supervision of the DBMS.

Abstract: A system and method operates with a document collection in which documents are represented as normalized document vectors. The document vector space is partitioned into a set of disjoint clusters and a concept vector is computed for each partition, the concept vector comprising the mean vector of all the documents in each partition. Documents are then reassigned to the cluster having their closest concept vector, and a new set of concept vectors for the new partitioning is computed. From an initial partitioning, the concept vectors are iteratively calculated to a stopping threshold value, leaving a concept vector subspace of the document vectors. The documents can then be projected onto the concept vector subspace to be represented as a linear combination of the concept vectors, thereby reducing the dimensionality of the document space.

Abstract: A direct access storage device (DASD) performs defect mapping and translates logical block address references to physical block addresses with a virtual track (VT) table and a virtual sector (VS) table, and also uses a prototype table (VSpr) that contains index locations for all virtual tracks that contain spares and identifies sectors located on the track, and a reassign table (VSre) that contains exceptions from the prototype table due to reassignment of a spare sector. The VS table contains index locations that identify a group of sectors located on the track corresponding to the index location, but does not include spares. The VT table includes columns that point into the VSpr and VSre tables. The overall size of the defect mapping tables is reduced by removing the spare sectors from the VS table, thereby more efficiently utilizing storage system resources.

Abstract: A system transfers data between a client computer and a server computer over a network, wherein communications are established over a first data link between the client and the server to provide the server with identification of the data to be transferred, then communications are established over a second data link between the client and the server for data transfer such that the second data link has a faster data transfer rate than the first data link, then the identified data is transferred from the client to the server; and then finally the client computer is provided with status information relating to the transfer of the identified data. The first data link is sufficient to support normal data operations utilizing existing network resources. The second data link can connect the clients to one or more of the servers, or may connect only particular clients and servers with special needs for large data transfer.

Abstract: A playback unit resembling a home audio component, retrieves audio data from a remote server and plays them back in real time, using a home audio system, in response to user selection. The playback unit provides an interface between a network source for audio material, such as the Internet, and a conventional home audio system for playback. The playback unit has a relatively simple operating system that does not require a lengthy boot-up sequence, cannot be accessed by the user, and does not require the launch of special software to initiate playback. Access to audio material and distribution rights can be controlled by network servers. In this to way, the playback unit can retrieve audio material from the network on demand, thereby vastly expanding the range of music available for playback, and can reproduce that music using the home audio system for high quality playback in a comfortable setting, with controlled access to audio material and controlled distribution and duplication of the material.

Abstract: A system and method associates a label and description with a search query such that the query, label, and description can be stored in a shared query repository so that queries can be retrieved by multiple users for reuse. The shared query repository can be searched, so that an appropriate query can be located, retrieved, and then submitted for execution over a document database by a search engine. Retrieved queries can be combined with other retrieved queries or modified with new search terms, and the new combined search query can be used for a new search on the database. The database search system and method efficiently permits reuse of search queries and facilitates sharing of search strategies.

Abstract: An Internet-based analysis tool follows, in real-time, the flow of traffic through a website. For every website page requested by a website visitor, the state of the visitor's browser is recorded and data relating to the path visitors take through the website is collected and studied. The state of the visitor's browser path is maintained in a traffic analysis cookie that is passed between a website file server and the visitor browser with every page requested for viewing. The cookie is maintained in a size that can be passed from server to browser and back again without negatively impacting server performance and without negatively impacting browser performance. The data in the cookie can follow the visitor browser through independent file servers, regardless of how the pages of a website might be distributed in storage.

Abstract: A dual element read/write head for a direct access storage device (DASD) positions the read and write elements relative to each other such that the same servo track can be used for read and write operations at the disk outside diameter (OD). As the head is moved across the disk from the OD toward the ID, different servo tracks are used for positioning the read and write elements in the same track as the head moves toward the disk ID. The STW TMR portion of the total TMR at the OD is thereby minimized to zero, so that the total TMR at the OD is primarily a function of only the conventional WW TMR and WR TMR components. The STW TMR gets larger as the head assembly moves toward the ID, so that the total TMR at the ID becomes a function of both the STW TMR and the remaining TMR components.

Abstract: A data cache is constructed with the same dimensions as for a conventional n-way associative cache, but is constructed as an (n−1)-way associative cache, so that one associative column of the cache is left unused, although the cache has the same memory array size as a typical n-way associative cache. The extra column of data in the cache is organized as an independent logical translation look-aside buffer (TLB) that is n-way associative. Thus, there is no separate TLB array for the cache, rather, the TLB is contained within the data cache array. In this way, the cache can be implemented with a single chip, and can be of relatively large size, on the order of 8 MB or more.

Abstract: A direct access storage device that (DASD) includes a sector servo control system that controls disk write operations by receiving a servo pattern readback signal in a sector, determining track centering for that sector, and generating a write inhibit signal before any write operations are initiated for that sector. The servo control system is able to make write inhibit decisions without software processing delays, enabling the system to produce a write inhibit signal quickly after an off-track excursion, and to terminate a write inhibit decision quickly after it is no longer needed.

Abstract: A digital broadcast system provides secure transmission of digital programs to in-home digital devices even when some of the devices are unauthorized. A matrix of device keys S.sub.j,i is provided, wherein "i" is a key index variable indicating a position in a key dimension of the matrix and "j" is a sets index variable indicating a position in a sets dimension of the matrix. Each in-home device is assigned plural device keys from the matrix, with one and only one device key for each key index variable "i" being assigned to a device. To generate a session key for a broadcast program, session numbers x.sub.i are encrypted with all device keys S.sub.j,i to generate a session key block which is decrypted by the in-home devices and used to generate a session key for decrypting the program.

Abstract: A method and apparatus for maintaining coherence between shared data stored within a plurality of memory devices, each memory device residing in a different node within a tightly coupled multiprocessor system. Each node includes a "local coherence unit" and an associated processor. A cache unit is associated with each memory/processor pair. Each local coherence unit maintains a table which indicates whether the most current copy of data stored within the node resides in the local memory, in the local cache, or in a non-local cache. The present invention includes a "global coherence" unit coupled to each node via the logical interconnect. The global coherence unit includes a interconnect monitoring device and a global coherence table. When data which resides within the memory of a first node is transferred to a second node, the interconnect monitoring device updates the global coherence table to indicate that the data is being shared.

Abstract: A disk drive system has a servo pattern with bursts that are recorded without multiple passes per burst and without trimming, so that the servo pattern bursts have the same width as the data tracks. The servo write steps occur in partial data track pitch (DTP) increments. A magneto-resistive (M-R) head is used to both record the servo pattern and transduce it. In a two-frequency system, relative gain calibration is performed using AGC circuitry to first calibrate one frequency and then the other. The resulting servo position error sensing (PES) signal has improved linearity and is simpler to write.

Abstract: An object oriented framework provides a set of objects that perform account management functioning and permits a framework user to add extensions to the framework for specific processing features, thereby producing an account management application program for managing the financial accounts of a company, including accounts receivable and accounts payable. The framework includes an Application category of classes that contains company information for general ledger processing, a Posting Combinations category of classes that define valid posting combinations for the general ledger, a Journals category of classes that create, process, validate, and post general ledger journals, a Bank Transactions category of classes that process bank statements, a Bank Statements and Reconciliation category of classes that reconcile bank statements with bank accounts, and a Closing category of classes that validate and close the current accounting period.

Abstract: An object oriented framework provides a set of objects that perform computer system server functions and that permit a framework user to add extensions for specific processing features, thereby producing a server program for managing computer system resources and performing desired functions. The framework includes a Server class of objects, which provides the server environment in which the objects performing server functions exist and serves as the primary interface between the server and the client machines, and includes a Service Object (SO) category of classes, whose objects comprise server function objects and implement two methods, one method called runMeFirst( ) and another method called runMeSecond( ) such that the runMeFirst( ) method is executed before the runMeSecond( ) method and interdependencies are resolved.

Abstract: A framework for use with object-oriented programming systems provides a reusable object oriented (OO) framework for use with object oriented programming systems that provides an information retrieval (IR) shell that permits a framework user to define an index class that includes word index objects and provides an extensible information retrieval system that evaluates a user query by comparing information contained in the user query with information contained in the word index objects that relates to stored documents. The information in word index objects is produced by preprocessing operations on documents such that the documents relevant to the user query will be identified, thereby providing a query result. The information retrieval system user can load documents into the computer system storage, index documents so their information can be subject to a query search, and request query evaluation to identify and retrieve documents most closely related to the subject matter of a user query.

Abstract: A framework for use with object-oriented programming systems provides a common message processing system structure that can be placed on any OOP platform and be configured to support any e-mail message protocol standard or specific mail server function. The framework defines an e-mail message as a number of distinct objects, each of which contains information that describes some portion of the message. All messages received by a system in which the framework is implemented are defined on this core object structure. Another set of objects and methods define the processing steps required for a mail server to process a message. A message is received as a class of message objects, which are assigned a message type that determines the subsequent processing steps to which the message object is subjected. As a message is processed, the objects of which it is comprised are changed, so that the message processing can be interrupted and then resumed without loss or duplication of processing steps.

Abstract: The magnetic states of MR reproducing heads are reinitialized during media drive manufacturing by applying initializing magnetic fields to the transducers after they have been manufactured and incorporated into media drive assemblies.

Abstract: A rechargeable photographic camera includes an interlock circuit that automatically inhibits operation of the camera flash when the camera is mated with a charging cradle, regardless of the condition of a manual on-off flash switch. The rechargeable battery of the camera therefore is assured of receiving a full charging current even if the flash unit is left on when the camera is mated with the charging cradle.

Abstract: An arrangement for controlling a zero crossing switch in order to connect a source of zero crossing AC voltage to and disconnecting it from an AC load line is disclosed herein along with its method of operation. To this end, means are provided for producing externally controlled command signals intended to control when the switch connects and disconnects the load line to and from the AC voltage. At the same time, a specific window of time is selected, which window begins a particular period of time prior to and includes at least certain zero crossing points of the AC voltage. Internally controlled command signals are produced in response to the AC voltage and externally controlled signals for actually controlling when the switch connects (ON) and disconnects (OFF) the load to and from the AC voltage.