Hewlett-Packard

About: Hewlett-Packard is a company organization based out in Palo Alto, California, United States. It is known for research contribution in the topics: Signal & Substrate (printing). The organization has 34663 authors who have published 59808 publications receiving 1467218 citations. The organization is also known as: Hewlett Packard & Hewlett-Packard Company.

System and method for maintaining consistent independent server-side state among collaborating servers

Abstract: A system and method are provided for maintaining consistent server-side state across a pool of collaborating servers with independent state repositories When a client performs an event on a collaborating server which affects such state on the server, it publishes notification of the event into a queue maintained in client-side state which is shared by all of the collaborating servers in the pool As the client makes requests to servers within the pool, the queue is thus included in each request When a collaborating server needs to access its server-side state in question, it first discerns events new to it from the queue and replicates their effects into such server-side state As a result, the effects of events upon server-side state are replicated asynchronously across the servers in the pool, as the client navigates among them

lmbench: portable tools for performance analysis

Abstract: lmbench is a micro-benchmark suite designed to focus attention on the basic building blocks of many common system applications, such as databases, simulations, software development, and networking. In almost all cases, the individual tests are the result of analysis and isolation of a customer's actual performance problem. These tools can be, and currently are, used to compare different system implementations from different vendors. In several cases, the benchmarks have uncovered previously unknown bugs and design flaws. The results have shown a strong correlation between memory system performance and overall performance. lmbench includes an extensible database of results from systems current as of late 1995.

High dislocation densities in high efficiency GaN‐based light‐emitting diodes

Abstract: The electrical, optical, and structural properties of light emitting diodes (LEDs) fabricated from the III–V nitride material system have been studied. LEDs with external quantum efficiencies as high as 4% were characterized by transmission electron microscopy and found to contain dislocation densities in excess of 2×1010 cm−2. A comparison to other III–V arsenide and phosphide LEDs shows that minority carries in GaN‐based LEDs are remarkably insensitive to the presence of structural defects. Dislocations do not act as efficient nonradiative recombination sites in nitride materials. It is hypothesized that the benign character of dislocations arises from the ionic nature of bonding in the III–V nitrides.

Clustering data streams: Theory and practice

Abstract: The data stream model has recently attracted attention for its applicability to numerous types of data, including telephone records, Web documents, and clickstreams. For analysis of such data, the ability to process the data in a single pass, or a small number of passes, while using little memory, is crucial. We describe such a streaming algorithm that effectively clusters large data streams. We also provide empirical evidence of the algorithm's performance on synthetic and real data streams.

What Is a Savitzky-Golay Filter? [Lecture Notes]

Abstract: This article has attempted to answer the question "What is a Savitky-Golay filter?" in terms that will be familiar to the DSP community and readers of IEEE Signal Processing Magazine. This article reviewed the definition and properties of S-G filters and showed how they can be designed easily using polynomial approximation of an impulse sequence. In contrast to most discussions of S-G filters, they focused on the frequency domain properties, and offered an approximate formula for the 3-dB cutoff frequency as a function of polynomial order N and impulse response half length M. Engineers with a frequency domain mindset may find this useful if they choose to use S-G filters in their application.