Abstract:
In a data processing system which includes a host (12) computer connected by a channel (28) interface unit through an input/output (30) interface and control (26) unit to an input/output (16) device, commands and data associated with the commands are received in a buffer (32) and first checked to determine whether the command has any pertinent data. If such check reveals that there is no pertinent data associated with a given command, that command is changed to an immediate command. Otherwise, the command is given a pointer in the buffer (32) which prioritizes the order in which it will be carried out. Where a command is determined to have no pertinent data associated with such command, and a previously buffered command still in the buffer (32) has pertinent data associated therewith, consolidation of the command is carried out in order to improve efficiency of the input/output (16) device.
Abstract:
An error signal is monitored to detect a change in the error signal greater than a predetermined limit and to tabulate the number of times the change in the error signal is in excess of the predetermined limit over a fixed period of time. Whenever the change in the error signal is in excess of the predetermined limit, it is reduced in magnitude to a predetermined value and this resultant signal is applied to the controlled apparatus (108) in place of the originally generated error signal. During each sampling time interval, the result of this comparison is used to increment or decrement a counter (110). If the count exceeds a predefined threshold, an alarm is actived.
Abstract:
A method and apparatus for loosely coupling a plurality of processors in a multiprocessor system to perform a coordinated task. The coordination of the task is implemented by an early start mode data transfer apparatus which coordinates the reading and writing of data files into and out of the data buffer (101) of the control unit (100) so that a data file can be written into the data buffer (101) while another file is concurrently being read out of the data buffer (101). Thus, both the host computer (130) and the associated tape drive units (140) can be active at the same time that data files are being read from or written into the data buffer (100) of the tape control unit (101).
Abstract:
A ribbon reverse mechanism for a high-speed line printer having a towel ribbon (12) driven between a pair of spring-loaded spools (14) by gear means (26) coupled to a band drive motor (18) includes an input shaft (30) coupled to the drive motor (18) and having mounted thereon a pair of spaced-apart worms (28) for driving respective gears (32). The gears (32) are each coupled to a wrap-spring clutch, housed within a clutch stop collar (34) having a plurality of teeth (46) engageable with a floating disk (42), to an output shaft (36) coupled to the spools (14). Each of the floating disks (42) are alternately engaged to its respective clutch stop collar (34), thereby permitting the wrap-spring clutch to be wound up, through energization of a coil (48). As one spool (14) becomes full, a ribbon direction sensor outputs a signal indicative thereof to a machine co-processor (40) in order that the active engagement coil (48) may be de-energized, while the inactive engagement coil (48) may be energized for reversing the direction of ribbon travel.
Abstract:
An optical recording structure (1) comprised of: an optically smooth and light reflecting substrate (2); the lower portion of a matrix material (3), selected from the group consisting of halocarbon polymers; a discontinuous stratum of light absorbing material (5), selected from the group consisting of low melting point semi-conductors, high melting point semi-conductors, high melting point refractory metals and common metals; the upper portion of the matrix material (4), selected from the same group as the lower matrix, and; if desired, a separate protective and hermetic sealing layer (17), and a dust defocusing overcoat (18). In operation, the stratum of light absorbing material (5), though discontinuous, is of sufficient density as to create an anti-reflective condition when the stratum (5) and the matrices (3 and 4) are tuned to the appropriate thicknesses. Upon irradiation by a focused laser beam of sufficient power, the stratum material (5) chemically reacts with the matrix material (3 and 4), destroying the interface (6) which allowed the anti-reflective condition to exist, thereby creating an optically transparent opening (9) which allows a read beam to reflect off the light reflecting substrate (2). Data is therefore recorded in the changes in the reflective condition of the recording structure (1).
Abstract:
A system and method of adaptively modifying the control signal of a servo system during a mode of acceleration or deceleration. An error accumulator (30), means generator (31), and feedforward generator (32) are used to generate a feedforward signal which modifies the control signal delivered to the servo motor (25). The feedforward signal for a given mode of operation is determined by the mean error during the previous operation in the mode and by the feedforward signal used during the previous operation in the same mode. Each subsequent operation in the same mode improves the feedforward signal until the mean error is minimized.
Abstract:
A method and system for sharing data and interrogating data include establishing a level of trust between mutually mistrusting entities so that data may be shared therebetween based on the level of trust. The method and system include interrogating data provided from one of the entities to the other entity without the receiving entity having complete access to the data associated therewith.
Abstract:
A system for reducing signal crosstalk in a flexible trace interconnect array includes a flexible dielectric material base, and a plurality of conductors longitudinally arranged as pairs in a signal layer array on the base. At least one of the pairs of conductors comprises a twisted pair.
Abstract:
Electronic mail is archived and retrieved based on metadata generated by the client sending the electronic mail. The metadata is generated based on variable metadata generation policies distributed to each client. The metadata generation policies are executed in each client in conjunction with each electronic mail sent from the client. The electronic mail is received in a mail server on route to at least one addressee of the electronic mail. The received electronic mail is processed based on the metadata attached to the received electronic mail.
Abstract:
The present invention provides a software-based solution for deploying virtual servers in a computer network. The method is initiated when an end user requesting a new virtual server clicks a hyperlink in which an imbedded command sequence requests the software to deploy a new virtual server. The software automatically updates the hypervisor environment to include the new virtual server, prepares the new virtual server disk allocations, propagates a server model image into the new virtual server, updates the new image with local identification parameters, and then boots the new virtual server.