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Association for Computing Machinery

Articles Tagged: Performance

Articles & Features

Volunteer computing

Volunteer computing

Computers continue to get faster exponentially, but the computational demands of science are growing even faster. Extreme requirements arise in at least three areas.

By David P. Anderson, March 2010

PDF | HTML | In the Digital Library

Volunteer computing

Volunteer computing

Computers continue to get faster exponentially, but the computational demands of science are growing even faster. Extreme requirements arise in at least three areas.

By David P. Anderson, March 2010

PDF | HTML | In the Digital Library

Clouds at the crossroads

Clouds at the crossroads

Despite its promise, most cloud computing innovations have been almost exclusively driven by a few industry leaders, such as Google, Amazon, Yahoo!, Microsoft, and IBM. The involvement of a wider research community, both in academia and industrial labs, has so far been patchy without a clear agenda. In our opinion, the limited participation stems from the prevalent view that clouds are mostly an engineering and business-oriented phenomenon based on stitching together existing technologies and tools.

By Ymir Vigfusson, Gregory Chockler, March 2010

PDF | HTML | In the Digital Library

Clouds at the crossroads

Clouds at the crossroads

Despite its promise, most cloud computing innovations have been almost exclusively driven by a few industry leaders, such as Google, Amazon, Yahoo!, Microsoft, and IBM. The involvement of a wider research community, both in academia and industrial labs, has so far been patchy without a clear agenda. In our opinion, the limited participation stems from the prevalent view that clouds are mostly an engineering and business-oriented phenomenon based on stitching together existing technologies and tools.

By Ymir Vigfusson, Gregory Chockler, March 2010

PDF | HTML | In the Digital Library

Scientific workflows and clouds

Scientific workflows and clouds

In recent years, empirical science has been evolving from physical experimentation to computation-based research. In astronomy, researchers seldom spend time at a telescope, but instead access the large number of image databases that are created and curated by the community [42]. In bioinformatics, data repositories hosted by entities such as the National Institutes of Health [29] provide the data gathered by Genome-Wide Association Studies and enable researchers to link particular genotypes to a variety of diseases.

By Gideon Juve, Ewa Deelman, March 2010

PDF | HTML | In the Digital Library

Are your friends who they say they are?

Are your friends who they say they are?

How sure are you that your friends are who they say they are? In real life, unless you are the target of some form of espionage, you can usually be fairly certain that you know whom your friends are because you have a history of shared interests and experiences. Likewise, most people can tell, just by using common sense, if someone is trying to sell them on a product, idea, or candidate. When we interact with people face-to-face, we reevaluate continuously whether something just seems off based on body language and other social and cultural cues.

By Roya Feizy, Ian Wakeman, Dan Chalmers, December 2009

PDF | HTML | In the Digital Library

Towards a user-friendly semantic formalism for natural language generation

Computational semantics has become an interesting and important branch of computational linguistics. Born from the fusion of formal semantics and computer science, it is concerned with the automated processing of meaning associated with natural language expressions [2]. Systems of semantic representation, hereafter referred to as semantic formalisms, exist to describe meaning underlying natural language expressions. To date, several formalisms have been defined by researchers from a number of diverse disciplines including philosophy, logic, psychology and linguistics. These formalisms have a number of different applications in the realm of computer science. For example, in machine translation a sentence could be parsed and translated into a series of semantic expressions, which could then be used to generate an utterance with the same meaning in a different language [14]. This paper presents two existing formalisms and examines their user-friendliness. Additionally, a new form of semantic representation is proposed with wide coverage and user-friendliness suitable for a computational linguist.

By Craig Thomas, December 2008

PDF | HTML | In the Digital Library

Geometric and path tracing methods for simulating light transport through volumes of water particles

The visual appearance of volumes of water particles, such as clouds, waterfalls, and fog, depends both on microscopic interactions between light rays and individual droplets of water, and also on macroscopic interactions between multiple droplets and paths of light rays. This paper presents a model that builds upon a typical single-scattering volume renderer to correctly account for these effects. To accurately simulate the visual appearance of a surface or a volume of particles in a computer-generated image, the properties of the material or particle must be specified using a Bidirectional Reflectance Distribution Function (BRDF), which describes how light reflects off of a material, and the Bidirectional Transmittance Distribution Function (BTDF), which describes how light refracts into a material. This paper describes an optimized BRDF and BTDF for volumes of water droplets, which takes their geometry into account in order to produce well-known effects, such as rainbows and halos. It also describes how a multiple-scattering path tracing volume integrator can be used to more accurately simulate macroscopic light transport through a volume of water, creating a more "cloudlike" appearance than a single-scattered volume integrator. This paper focuses on replicating the visual appearance of volumes of water particles, and although it makes use of physical models, the techniques presented are not intended to be physically accurate.

By James Hegarty, September 2008

PDF | HTML | In the Digital Library

Comparison of input devices and displays for protein visualization

By Elke Moritz, Thomas Wischgoll, Joerg Meyer, December 2005

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Introduction

By William Stevenson, October 2005

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Game-state fidelity across distributed interactive games

By Aaron McCoy, Declan Delaney, Tomas Ward, October 2005

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Game-state fidelity across distributed interactive games

By Aaron McCoy, Declan Delaney, Tomas Ward, October 2005

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Introduction

By William Stevenson, August 2005

PDF | HTML | In the Digital Library

An interaction model for mobile agent services using social networks

By Vishakh, Nicholas Urrea, Tadashi Nakano, Tatsuya Suda, August 2005

PDF | HTML | In the Digital Library

Overcoming misbehavior in mobile ad hoc networks

By George Athanasiou, Leandros Tassiulas, Gregory S. Yovanof, August 2005

PDF | HTML | In the Digital Library

Overcoming misbehavior in mobile ad hoc networks

By George Athanasiou, Leandros Tassiulas, Gregory S. Yovanof, August 2005

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Experimental mobile gateways

By Premshree Pillai, August 2005

PDF | HTML | In the Digital Library

Experimental mobile gateways

By Premshree Pillai, August 2005

PDF | HTML | In the Digital Library

Game-state fidelity across distributed interactive games

By Aaron McCoy, Declan Delaney, Tomas Ward, June 2003

PDF | HTML | In the Digital Library

Building an MPI cluster

By Donald C. Bergen, Boise P. Miller, August 2002

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Optimizing application performance

By M. Tyler Maxwell, Kirk W. Cameron, August 2002

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Connector

By Kostas Pentikousis, July 2001

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Connector

By Kostas Pentikousis, July 2001

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Graphic libraries for Windows programming

By M. Carmen Juan Lizandra, June 2000

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Objective viewpoint

By Matt Tucker, March 2000

PDF | HTML | In the Digital Library

Design of an interactive tutorial for logic and logical circuits

By Jeremy Kindy, John Shuping, Patricia Yali Underhill, David John, March 2000

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Prefix compression of sparse binary strings

Note from ACM Crossroads: Due to errors in the layout process for printing on paper, the version of this article in the printed magazine contained several errors (mostly related to superscripts). This HTML version is the accurate version. Please refer to this HTML version instead of the printed version and accept our apologies for any inconvenience.

By David Salomon, March 2000

PDF | HTML | In the Digital Library

A hierarchical error controlled octree data structure for large-scale visualization

By Dmitriy V. Pinskiy, Joerg Meyer, Bernd Hamann, Kenneth I. Joy, Eric Brugger, Mark Duchaineau, March 2000

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Ask Jack

By Jack Wilson, March 2000

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Introduction

By Kevin Fu, September 1999

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Objective viewpoint

By George Crawford, September 1999

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Linux DSP shell

By Michael Stricklen, Bob Cummings, Brandon Bonner, September 1999

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Introduction to Linux networking and security

By Wei-Mei Shyr, Brian Borowski, September 1999

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Parallel computing with Linux

By Forrest Hoffman, William Hargrove, September 1999

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The Texas Tech tornado cluster

By Per Andersen, September 1999

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Introduction

By Alessio Lomusico, June 1999

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Where do intelligent agents come from?

By Cristobal Baray, Kyle Wagner, June 1999

PDF | HTML | In the Digital Library

Protecting the integrity of agents

By Michael J. Grimley, Brian D. Monroe, June 1999

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