Showing papers by "Hewlett-Packard published in 1994"

An introduction to disk drive modeling

Abstract: Although disk storage densities are improving impressively (60% to 130% compounded annually), performance improvements have been occurring at only about 7% to 10% compounded annually over the last decade. As a result, disk system performance is fast becoming a dominant factor in overall svstem behavior. Naturally, researchers want to improve overall I/O performance, of which a large component is the performance of the disk drive itself. This research often involves using analytical or simulation models to compare alternative approaches, and the quality of these models determines the quality of the conclusions: indeed, the wrong modeling assumptions can lead to erroneous conclusions. Nevertheless, little work has been done to develop or describe accurate disk drive models. This may explain the commonplace use of simple, relatively inaccurate models. We believe there is much room for improvement. This article demonstrates and describes a calibrated, high-quality disk drive model in which the overall error factor is 14 times smaller than that of a simple first-order model. We describe the various disk drive performance components separately, then show how their inclusion improves the simulation model. This enables an informed trade-off between effort and accuracy. In addition, we provide detailed characteristics for two disk drives, as well as a brief description of a simulation environment that uses the disk drive model. >

Object-oriented development: the fusion method

Abstract: 1. Introduction. 2. Analysis Models and Notations. 3. Process of Analysis. 4. Design. 5. Implementation. 6. Case Study. 7. Exercises. 8. Fusion and Other Methods. 9. Reuse. 10. Managing a Fusion Project. Appendix A: Fusion Process Summary. Appendix B: Fusion Notation Summary. Appendix C: Fusion Reference.

Iterative module scheduling: an algorithm for software pipelining loops

Abstract: Module scheduling is a framework within which a wide variety of algorithms and heuristics may be defined for software pipelining innermost loops. This paper presents a practical algorithm, iterative module scheduling, that is capable of dealing with realistic machine models. This paper also characterizes the algorithm in terms of the quality of the generated schedules as well the computational expense incurred.

Video on demand system with multiple data sources configured to provide VCR-like services

Abstract: A video server for providing Video-On-Demand is disclosed. A plurality of data sources are coupled individually to a first and second bi-directional data/instruction switch. The first switch is additionally coupled to a data storage system and the second switch is coupled to a network interface. A real time controller is coupled to the data sources and the switches and can couple any part of the data storage system to any selected data source and any given network channel to any selected data source. A control system coupled to the real time controller and the second switch provides support services to the real time controller and acts as a gateway to third party services and products. The data storage system is largely comprised of disk drive arrays. Video data is striped across the individual arrays, each video data program that a user requests being striped across one array. Each array provides video data to many users through the data sources. The video server is tolerant of individual failures in the data storage system and among the data sources, as operating portions of the data storage system and spare data sources can be rapidly switched to substitute for failed units. The server can also be readily expanded and provides a user experience similar to that of a video cassette recorder.

A Centering Approach to Pronouns

Abstract: In this paper we present a formalization of the centering approach to modeling attentional structure in discourse and use it as the basis for an algorithm to track discourse context and bind pronouns. As described in Grosz, Joshi and Weinstein (1986), the process of centering attention on entities in the discourse gives rise to the intersentential transitional states of continuing, retaining and shifting. We propose an extension to these states which handles some additional cases of multiple ambiguous pronouns. The algorithm has been implemented in an HPSG natural language system which serves as the interface to a database query application.

Flexible patient monitoring system featuring a multiport transmitter

Abstract: A flexible patient monitoring system which interfaces a telemetry subsystem with a network by way of a telemetry transmission receiving system and a network controller. The telemetry subsystem includes one or more monitoring instruments, a multiport transmitter, a telemetry subsystem interface, a backchannel receiver module, and a telemetry docking station. The flexible patient monitoring system may be configured to operate in at least four modes: ambulatory telemetry mode, wherein the multiport transmitter is operated independently of other monitoring instruments and is powered by an internal power source; docked telemetry mode, wherein the multiport transmitter is connected to the telemetry docking station for transfer of data and power; simple instrument telemetry mode, wherein the multiport transmitter and a primary monitoring instrument or an auxiliary monitoring instrument are connected together for transfer of data; and docked instrument telemetry mode, wherein the multiport transmitter and a primary monitoring instrument or an auxiliary monitoring instrument are attached to the telemetry docking station for transfer of data (and optionally for transfer of power to the multiport transmitter). Wireless communications between the telemetry subsystem and various nodes on the network are thus enabled. Information may be provided to and from the telemetry subsystem interface via the multiport transmitter.

Informal workplace communication: what is it like and how might we support it?

Abstract: We present new findings about the nature of informat communications, derived from a naturalistic study of people’s everyday working activities. We identify why such interactions are so common, and valuable and how they are achieved in the workplace. We also address weaknesses in current systems that support such interactions remotely and identify further requirements for better support. We also discuss the implications of this work for conversational theories.

Printer/client network with centrally updated printer drivers and printer status monitoring

Abstract: A network includes plural client processors, a file server and plural printers. Each client processor has memory that stores a printer driver procedure which enables the client processor to interface with at least one printer type. The file server includes memory for storing a most updated printer driver procedure for each printer type coupled to the file server. The file server is responsive to a print request from a client processor to assign a printer to the requesting client processor. The file server then in combination with the client processor determines if a printer driver procedure for the assigned printer in the client processor is identical to a most updated printer driver procedure stored in memory in the file server. If not, the file server enables alteration of the printer driver procedure in the client processor to bring it into coincidence with the most updated print driver procedure. A printer utility is also installed in each client processor and provides the means for automatically determining network status and for indicating to the user whether the network is available or unavailable, and a message indicating the reason for the unavailability.

Effects of reuse on quality, productivity, and economics

Abstract: This article presents metrics from two Hewlett-Packard (HP) reuse programs that document the improved quality, increased productivity, shortened time-to-market, and enhanced economics resulting from reuse. Work products are the products or by-products of the software-development process: for example, code, design, and test plans. Reuse is the use of these work products without modification in the development of other software. Leveraged reuse is modifying existing work products to meet specific system requirements. A producer is a creator of reusable work products, and the consumer is someone who uses them to create other software. Time-to-market is the time it takes to deliver a product from the time it is conceived. Experience with reuse has been largely positive. Because work products are used multiple times, the accumulated defect fixes result in a higher quality work product. Because the work products have already been created, tested, and documented, productivity increases because consumers of reusable work products need to do less work. However, increased productivity from reuse does not necessarily shorten time-to-market. To reduce time-to-market, reuse must be used effectively on the critical path of a development project. Finally, we have found that reuse allows an organization to use personnel more effectively because it leverages expertise. However, software reuse is not free. It requires resources to create and maintain reusable work products, a reuse library, and reuse tools. To help evaluate the costs and benefits of reuse, we have developed an economic analysis method, which we have applied to multiple reuse programs at HP. >

Process enaction and tool integration via a task oriented paradigm

Abstract: A task manager for providing personal organization, project management, and process automation capabilities. The task manager maintains a hierarchical list of tasks for an individual. For each task, notes can be kept, priorities set, and progress tracked. Also, subsets of the task hierarchy can be shared. Every task in the task manager belongs to a class, and each class includes pre-defined automatic actions and manual actions. The pre-defined automatic actions are automatically executed by the task manager when the task is being worked on. The manual actions aid in task execution because the relevant operations (that is, the manual actions) are available when the task is being worked on. The task manager communicates with agents, tools, and process engines via a message system. The agents, tools, and process engine may receive task information from the task manager and may also remotely control the task manager.

Wafer bonding of light emitting diode layers

Abstract: A method of forming a light emitting diode (LED) includes providing a temporary growth substrate that is selected for compatibility with fabricating LED layers having desired mechanical characteristics. For example, lattice matching is an important consideration. LED layers are then grown on the temporary growth substrate. High crystal quality is thereby achieved, whereafter the temporary growth substrate can be removed. A second substrate is bonded to the LED layers utilizing a wafer bonding technique. The second substrate is selected for optical properties, rather than mechanical properties. Preferably, the second substrate is optically transparent and electrically conductive and the wafer bonding technique is carried out to achieve a low resistance interface between the second substrate and the LED layers. Wafer bonding can also be carried out to provide passivation or light-reflection or to define current flow.

Microstructure and mechanical properties of Pb-free solder alloys for low-cost electronic assembly: A review

Abstract: Lead-free solders, including Sn-58Bi, Sn-52In, and Sn-3.5Ag, are potential replacements for Sn-37Pb solder in low-cost electronic assembly. This paper reviews the literature on the microstructure and mechanical properties of these alloys. Because of the processing and testing conditions, many of the data are not predictive for electronic assembly applications. However, eutectic Sn-Bi seems to have properties approaching those of eutectic Sn-Pb under most conditions, while eutectic Sn-In seems far inferior in most respects. Eutectic Sn-Ag has many promising characteristics, but its relatively high melting temperature may preclude its use for this type of application.

Patient monitoring system

Abstract: A method is described for attaching a monitoring device to a patient comprising providing a fastener having a frame defining an opening adapted to receive a reel in a button hole fashion; inserting the reel behind a portion of the patient's clothing; positioning the frame on the opposite side of the portion of the patient's clothing relative to the reel and inserting the reel into the opening trapping the portion of material between the reel and the frame; and attaching the monitoring device to the fastener by a tether.

Multiple light emitting diode module

Abstract: A LED module for providing a source of illumination comprises a plurality of LED lamps each having an anode lead and a cathode lead for providing electrical and mechanical connection. The anode lead of each LED lamp is connected to an anode bus bar and the cathode lead of each LED lamp is connected to a cathode bus bar by solderless connection. The bus bars and the leads of each LED lamp may be integral with each other. Alternatively, the bus bars and leads may be non-integral with each other, connected by an interlocking interaction or interference fit between approximately complementary portions of each lead and bus bar. The LED module may accommodate serial electrical interconnection with other LED modules, it may be shaped according to the particular contour or design of an accommodating light assembly, and it may comprise LED lamps placed at arbitrary positions to achieve a predetermined degree of illumination.

An open-systems approach to video on demand

Abstract: Open systems will enable video servers and set-tops to provide different services in a variety of environments Hewlett-Packard is interested in applying the principles of open systems to video on demand (VOD) In particular, the company is developing a technology base that will allow their servers and set-tops to operate in a variety of environments and enable the provision of a variety of services The impact that the different VOD system elements have on the video server and set-top are examined from a communications standpoint Opportunities for open or standard interfaces are identified and recommendations are made on what these should be where possible >

The Khoros software development environment for image and signal processing

Abstract: Data flow visual language systems allow users to graphically create a block diagram of their applications and interactively control input, output, and system variables. Khoros is an integrated software development environment for information processing and visualization. It is particularly attractive for image processing because of its rich collection of tools for image and digital signal processing. This paper presents a general overview of Khoros with emphasis on its image processing and DSP tools. Various examples are presented and the future direction of Khoros is discussed. >

Generalized rate-monotonic scheduling theory: a framework for developing real-time systems

Abstract: Real-time computing systems are used to control telecommunication systems, defense systems, avionics, and modern factories. Generalized rate-monotonic scheduling theory, is a recent development that has had large impact on the development of real-time systems and open standards. In this paper we provide an up-to-date and self-contained review of generalized rate-monotonic scheduling theory. We show how this theory can be applied in practical system development, where special attention must be given to facilitate concurrent development by geographically distributed programming teams and the reuse of existing hardware and software components. >

Unit print head assembly for ink-jet printing

Abstract: Ink-jet pens having multiple print heads are manufactured with readily replaceable unit print head assemblies that facilitate testing of print head performance prior to complete assembly of the pen.

System and method for revaluation of stored tokens in IC cards

Abstract: A terminal (30) for carrying out at a private location a transaction consisting of alteration of a token value stored in an IC card (12) issued to a cardholder via an on-line transaction session with an operatively compatible terminal at a remote location. The private terminal (30) establishes data links with the IC card (12) and the remote terminal (30) and passes secure authentication and transaction messages between them via these data links, relying on the IC card (12) and the remote terminal (30) for message security.

Protective capping apparatus for an ink jet pen

Abstract: An ink pen is provided with a protective capping apparatus to protect against damage caused by the ingress of dirt and debris, the accumulation or solidification of ink, the discharge of static electricity or the like. The protective capping apparatus has a protective cap movable between an open position and a closed position. In the closed position the protective cap shields a portion of an ink pen such as the ink-jets or the electrical contacts.

Data processing system and method for automatically performing prioritized nursing diagnoses from patient assessment data

Abstract: A data processing system and method for automatically performing prioritized nursing diagnoses from patient assessment data stores a diagnosis table containing relations between nursing diagnoses and patient characteristics, with each such relation having a corresponding probability measure. A priority table containing at least one relation between a diagnosis from a diagnosis table and a corresponding priority measure is also stored. The data processing system receives assessment data, matches assessment data with relations in the diagnosis table and constructs a potential diagnosis list including the matched diagnoses and the corresponding probability measures. The probability measure of each diagnosis in the potential diagnosis list is weighted with the priority measure corresponding to the diagnosis from the priority table. When more than one relation is provided for a diagnosis in the diagnosis table, probability measures are combined when the potential diagnosis list is constructed. The probability measures are preferably added together to combine them, and are preferably limited to a maximum value, for example, equivalent to 99%. The diagnosis table may be divided into primary and secondary diagnoses tables. Each relation in the primary diagnosis table has the same probability measure. The tables and lists of the data processing system and method preferably implemented in a relational database.

Dynamic control of a patient monitoring system

Abstract: A flexible patient monitoring system which interfaces a telemetry subsystem with a network by way of a telemetry transmission receiving system and a network controller. The telemetry subsystem includes one or more monitoring instruments, a multiport transmitter, a telemetry subsystem interface, a backchannel receiver module, and a telemetry docking station. The flexible patient monitoring system may be operated to implement network-based, system-originated control of one or more of the patient monitoring functions performed in the system. A particular function that is subject to dynamic control is the transmission of a telemetry signal.

Computer system manager for monitoring events and operating parameters and generating alerts

Abstract: A system manager for a computer system. The system manager transparently monitors signals transferred between computer system components along a system bus and stores objects related to the monitored signals in an object space. Information related to operating conditions within the system can then be provided from the object space. Later, the object space can be updated and the updated object space used to provide updated information regarding the operating conditions of the system.

Method for licensing software

Abstract: Disclosed is a system that provides a common application software interface for a variety of vendor supplied license servers. The system provides a single set of program calls and translates this single set of calls into a set of calls for each license server. This translation is performed using a translate table, which is easily updated to interface to newly developed or newly released license servers. The system runs as a separate process within the operating environment to monitor the application program, and as long as the application program continues to provide services to the user, the system sends periodic license renewal messages to the license server. The system also notifies the user when the application program cannot obtain a license in order to provide a consistent user interface across applications.

Method of bumping substrates by contained paste deposition

Abstract: A solder bump is stenciled into a substrate, providing bumped substrate at pitches below 400 microns. The solder is applied through stencil/mask and paste method; the mask, however, remains attached to the substrate during reflow. Pitches of greater than 400 microns may also be obtained through the invention. The invention further provides for generation of uniform, controllable volume metal balls

Memory systems with data storage redundancy management

Abstract: A disk array (10) has a plurality of disks (12), a disk array controller (14) for coordinating data transfer to and from the disks, and a RAID management system (16) for mapping two different RAID areas (42,44) onto the disks. The RAID management system (16) stores data in one of the RAID areas according to mirror redundancy, and stores data in the other RAID area according to parity redundancy. The RAID management system (16) then shifts or migrates data between the mirror and parity RAID areas on the disks in accordance with a predefined performance protocol, such as data access recency or access frequency. A method for managing data on a disk array is also disclosed.

Embedded hidden identification codes in digital objects

Abstract: A method and apparatus for encoding identification information into a stream of digital data representing an object. The digital data representing an object is modified to add embedded identification information into the data. This modification is done such that the resultant changes to the object are not objectionable to the user. By comparing the original digital data to the modified data, the possessor of the original data can recover the embedded identification information. However the identification information is effectively unavailable to anyone not possessing the original data.

Saving power by synthesizing gated clocks for sequential circuits

Abstract: Portable devices demand low power consumption to prolong battery life. Gating the clock is one strategy for saving power. The authors' technique identifies self-loops in an FSM and uses the function described by the self-loops to gate the clock. Applying these techniques to standard benchmarks achieved an average 25% less power dissipation at a cost of only 5% more area. >