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Primeur weekly 2011-12-12

Desktop Grids

Charity Engine is now live

The Cloud

Platform Computing dramatically simplifies private Cloud management for enabling enterprise Platform-as-a-Service

CBN pilots new Cloud computing services in Indonesia with Brocade

Cisco introduces CloudVerse, an end-to-end framework to build, nanage and connect Clouds

Dell Boomi announces development of Cloud-based master data management solution; Unifying data across applications in the Cloud

HP and Box accelerate business collaboration in the Cloud

Elders Australia signs outsourcing agreement with HP

HP and Microsoft deliver global communications and collaboration solutions via the Cloud

IBM unveils analytics solution to help clients extract insight from patents and intellectual property

IBM to acquire DemandTec to expand Cloud-based analytics for Smarter Commerce

Oracle releases Oracle Solaris Cluster 4.0

EuroFlash

Action plan on making research data accessible

Managing dataflows

Boeing buys site license for Bright Cluster Manager

New 38.8 Tflops cluster opens at the University of Bordeaux

PlanetHPC issues strategy report

EMEA server market grows by 0.6% in 3Q11 to $3.2 billion as server revenues topple in Western Europe and in Middle East and Africa

USFlash

Make room for Stampede: TACC expands data centre for new supercomputer

Supercomputer reveals new details behind drug-processing protein model

NC State team to develop energy efficient 3D CPU

Computer simulations shed light on the physics of rainbows

The Green Grid expands its network in Asia by establishing a presence in China

Centre for High Performance Computing places South Africa back in TOP500 supercomputer list

HP named a leader in Magic Quadrant for Midrange and High-end Modular Disk Arrays

HP increases revenue opportunities for Channel Partners in networking

Researchers demonstrate future of computing with graphene, Racetrack and carbon nanotube breakthroughs

Intel and Micron extend NAND Flash technology leadership with introduction of world's first 128Gb NAND device and mass production of 64Gb 20nm NAND

NVIDIA directives-based GPU computing programme already delivering application speed-ups of 5x and more

Raritan Data Center Infrastructure Management (DCIM) solution at Gartner Conference

Computer simulations shed light on the physics of rainbows

6 Dec 2011 San Diego - Computer scientists at UC San Diego, who set out to simulate all rainbows found in nature, wound up answering questions about the physics of rainbows as well. The scientists recreated a wide variety of rainbows - primary rainbows, secondary rainbows, redbows that form at sunset and cloudbows that form on foggy days - by using an improved method for simulating how light interacts with water drops of various shapes and sizes. Their new approach even yielded realistic simulations of difficult-to-replicate "twinned" rainbows that split their primary bow in two.

UC San Diego alumnus Iman Sadeghi, who did the work while a Ph.D. student at the Jacobs School of Engineering, his advisor, computer science professor Henrik Wann Jensen, and scientists from Spain, England and Switzerland, are set to publish their findings inACM Transactions on Graphicsin December of this year.

"This goes beyond computer graphics", Henrik Wann Jensen stated. "We now have an almost complete picture of how rainbows form."

Henrik Wann Jensen is no stranger to advances in computer graphics. He earned an Academy Award in 2004 for research that brought life-like skin to animated characters. He has worked on a number of Hollywood blockbusters, including James Cameron's "Avatar".

Henrik Wann Jensen, Iman Sadeghi and colleagues originally set out to simulate rainbows to better understand how spherical water drops interact with light, resulting in the bright, multi-coloured arcs that we are used to seeing when rain stops or in tropical, humid weather. They were hoping to improve techniques used in animated movies and video games.

"You usually don't get the opportunity to study such beautiful phenomena while working on your Ph.D. thesis", stated Iman Sadeghi, who is now a software engineer in the graphics division of Google in Santa Monica. "There is a lot more to rainbows than meets the eye."

As they started running various simulations, the scientists realized that the interaction of light with spherical drops could not explain some kinds of rainbows, such as twinned rainbows. Scientists turned to research showing that, as a water drop falls, air pressure flattens the bottom of it and shapes it like a burger. Henrik Wann Jensen and his team called these slightly deformed water drops "burgeroids". "It's not a very mathematical term, but we like to use it", Henrik Wann Jensen stated. Simulations based on the so-called burgeroids, rather than on spherical drops of water, allowed the researchers to replicate a wide range of rainbows found in nature. "We are the first to present an accurate simulation of twinned rainbows", Iman Sadeghi stated.

The basic mechanism behind the formation of rainbows has been well understood for hundreds of years: A beam of light is both reflected and refracted within the water drop, and becomes strongly concentrated near the "rainbow angle" in the drop. The rainbow angle changes with the colour of the light. As a result, sunlight separates into its spectral components, forming the colours we see in the sky. "The variation in the appearance of rainbows is due to the size and shape of rain drops", Iman Sadeghi stated.

It is surprising that the physics of rainbows are still not completely understood, Henrik Wann Jensen said. In the past, eminent scientists, including Isaac Newton and French mathematician Rene Descartes, made calculations and conducted experiments to explain how rainbows form. But today, funding for rainbow research is scarce and so is work on the topic.

Henrik Wann Jensen's quest to learn about the physics of rainbows led him to the Light and Color in Nature conference at St. Mary's College in St. Mary's City, Maryland. He served as keynote speaker and met Philip Laven, an internationally renowned expert on rainbows, who became one of the study's co-authors.

Until now, most simulations of rainbows had assumed that water drops are spherical, which isn't true for large rain drops, Philip Laven said. In this paper, researchers have adopted a completely different approach and developed a more realistic model to recreate rainbows, he said.

"The simulations shown in this paper offer the prospect of a better understanding of real rainbows", Philip Laven stated. "I hope that the next step will be to use these new techniques for a systematic investigation of rainbows caused by realistically shaped rain drops."

Henrik Wann Jensen, Iman Sadeghi, Philip Laven and their colleagues plan to present their findings at the SIGGRAPH conference in 2012, which will take place in Los Angeles. Henrik Wann Jensen also plans to attend the next Light and Color in Nature conference, which will take place in Alaska. Will he try to simulate the Northern Lights next? He just might, he said.
Source: University of California - San Diego

Back to Table of contents

Primeur weekly 2011-12-12

Desktop Grids

Charity Engine is now live

The Cloud

Platform Computing dramatically simplifies private Cloud management for enabling enterprise Platform-as-a-Service

CBN pilots new Cloud computing services in Indonesia with Brocade

Cisco introduces CloudVerse, an end-to-end framework to build, nanage and connect Clouds

Dell Boomi announces development of Cloud-based master data management solution; Unifying data across applications in the Cloud

HP and Box accelerate business collaboration in the Cloud

Elders Australia signs outsourcing agreement with HP

HP and Microsoft deliver global communications and collaboration solutions via the Cloud

IBM unveils analytics solution to help clients extract insight from patents and intellectual property

IBM to acquire DemandTec to expand Cloud-based analytics for Smarter Commerce

Oracle releases Oracle Solaris Cluster 4.0

EuroFlash

Action plan on making research data accessible

Managing dataflows

Boeing buys site license for Bright Cluster Manager

New 38.8 Tflops cluster opens at the University of Bordeaux

PlanetHPC issues strategy report

EMEA server market grows by 0.6% in 3Q11 to $3.2 billion as server revenues topple in Western Europe and in Middle East and Africa

USFlash

Make room for Stampede: TACC expands data centre for new supercomputer

Supercomputer reveals new details behind drug-processing protein model

NC State team to develop energy efficient 3D CPU

Computer simulations shed light on the physics of rainbows

The Green Grid expands its network in Asia by establishing a presence in China

Centre for High Performance Computing places South Africa back in TOP500 supercomputer list

HP named a leader in Magic Quadrant for Midrange and High-end Modular Disk Arrays

HP increases revenue opportunities for Channel Partners in networking

Researchers demonstrate future of computing with graphene, Racetrack and carbon nanotube breakthroughs

Intel and Micron extend NAND Flash technology leadership with introduction of world's first 128Gb NAND device and mass production of 64Gb 20nm NAND

NVIDIA directives-based GPU computing programme already delivering application speed-ups of 5x and more

Raritan Data Center Infrastructure Management (DCIM) solution at Gartner Conference