Engineers at the University of Arizona are looking to bats as role models. They specifically want to study the flying mammals' navigation systems as the base for the advanced radar systems they're looking to create.

"Bats do exactly what we're trying to do," said Nathan Goodman, an assistant professor of electrical and computer engineering at the school in Tucson, Ariz. "They have cognitive sonar and we're developing cognitive radar, which is in the electromagnetic spectrum."

Engineers at the University of Arizona are studying bat sonar as they work on computer models for their own cognitive radar systems.

Goodman is now at work on the mathematical framework for cognitive radar, which will use multiple systems to send out multiple waveforms. The systems will work together to measure the environment more quickly than non-cognitive systems can.

Cognitive radar's intelligence is built on a statistical method called Bayesian analysis, Goodman said. The receiver has prior knowledge of what it's looking for—perhaps a terrain map, the likely targets to be found in that terrain, and a history of movements in that area. Then it forms a number of hypotheses about what may be out there based on the first transmitted signals.

Currently, Goodman and his students are working with computer simulations.

"Eventually, extracting data and properly analyzing it in a real-world situation will be a very challenging part of the research," he said.

Yet bats are able to carry out all this recognition and analysis with a brain that's smaller than a golf ball.

"I don't think the bat is doing Bayesian equations in its head," Goodman said. "But it is constantly updating what it thinks is true about its environment."

Although engineers are still a long way from developing radars with the sophisticated capabilities of bat echo-location, looking at how bats function is a good way to understand what cognitive radar is all about.

Bats use different chirps as they scan for, identify, and approach a target, said Goodman, who is developing similar strategies for adapting waveforms dynamically in response to echo data returned from a target.

Researchers recently cracked several widely used security systems used to encrypt computers. The systems include Microsoft's BitLocker, Apple's FileVault, and Linux's dm-crypt.

In the process, they discovered several things that computer owners can do to protect their hard drives against a security breach. They also found that, sometimes, owners are pretty much powerless to protect their computers.

The security measure that the Princeton University researchers breached is called disk encryption, which is meant to keep information stored in a computer's permanent memory safe. It's often used for laptops, according to Alex Halderman, a Ph.D. candidate in the computer science department at Princeton University.

"We've broken disk encryption systems in exactly the case when they seem to be most important these days: laptops that contain sensitive corporate data or personal information about business customers," Halderman said. "Unlike many security problems, this isn't a minor flaw; it is a fundamental limitation in the way these systems were designed."

An attack like those staged by the team is particularly effective against computers that are turned on but locked, such as laptops that are in sleep mode. One effective countermeasure is to turn off a computer entirely. But in some cases even that doesn't protect the computer, Halderman and his team found.

The findings demonstrate the risks associated with recent high-profile laptop thefts, including a University of California, Berkeley laptop that contained information on more than 98,000 graduate students, said Edward Felten, the director of the Center for Information Technology Policy at Princeton.

Although many officials believe that disk encryption would protect sensitive information in these instances, the new research demonstrates that the information could easily be read, even when data is encrypted, Felten said.

"Our results show that disk encryption provides less protection than previously thought," he said. "Even encrypted data can be vulnerable if an intruder gets access to the laptop."

Disk encryption technologies rely on the use of secret keys— essentially, large random numbers—to encode and protect information. Computers need these keys to access files stored on their own hard disks or other storage systems. Once an authorized user has typed in a password, computers typically store the keys in the temporary RAM so that protected information can be accessed regularly. The keys are meant to disappear as soon as the RAM chips lose power.

The team wrote programs that gained access to essential encryption information automatically after cutting power to machines and rebooting them. The method worked when the attackers had physical access to the computer and when they accessed it remotely over a computer network.

The attack even worked when the encryption key had already started to decay, because the researchers were able to reconstruct it from multiple derivative keys that were also stored in memory, Felten said.

Experiments conducted at Purdue University's new hydrogen facility aim to help NASA develop rockets faster and less expensively for future missions to Mars and the moon.

A more efficient cooling mechanism could improve performance and reduce the need for costly overhauls, said William Anderson, an associate professor in Purdue's School of Aeronautics and Astronautics in West Lafayette, Ind.

James Sisco, a doctoral student in Purdue's School of Aeronautics and Astronautics, assembles portions of an experiment to study unstable combustion inside rocket engines.

Liquid hydrogen acts as a coolant before it enters the combustion chamber. The frigid liquid hydrogen, about -420°F, circulates through channels in a cooling jacket surrounding the combustor, absorbing heat and raising its temperature before being injected into the combustion chamber.

The Purdue research focuses on accurately measuring the heat flux, which is caused by differences in temperature between the hot combustion gases and the cooled walls of the combustor. Combusted gases in the rocket's chamber reach 6,000°F.

The measurements are used to improve detailed computational models of how propellants mix inside the combustor. The work also aims at better understanding the behavior of coolant inside channels surrounding the combustor, Anderson said.

Nordic Windpower Ltd. of San Francisco has implemented a product lifecycle management system to help roll out its two-blade, utility-scale wind turbines

The company recently installed Arena PLM, from Arena Solutions Inc. of Foster City, Calif., to track product launch goals and collaborate with contract manufacturing partners around the world.

"Because our wind turbines weigh less than three-blade models, they also cost less to produce. By using PLM, we'll be able to further reduce our costs from design through manufacturing," said Greg Mead, vice president of manufacturing and operations at Nordic Windpower.

When it comes to motorcycle helmets, one size doesn't fit all and no size fits everyone. Many riders resign themselves to buying a slightly too-large or too-small helmet.

But officials at the European Custom Fit project feel that vital head protection should be perfectly sculpted to the wearer. The project, funded by the European Commission, is a consortium made up of 32 partners from 12 countries. It aims to advance European rapid-prototyping technology.

Members are now investigating ways to make cost-effective customized consumer goods. Their current focus is on motorcycle helmets.

The customized helmet can increase the level of safety by lessening the tendency of the helmet to be pulled off the head during riding, according to a Custom Fit statement.

The customized helmet process first calls upon a three-dimensional scanner, which scans the user's head to capture its exact geometry. The project uses a scanner from Human Solutions of Kaiserslautern, Germany.

Next, using specialized computer-aided design software from Delcam of Birmingham, England, designers adapt the digital product design to the consumer's head, as captured by the scanner. Finally, the customized part is manufactured via a specialized rapid manufacturing method developed by De Montfort University of Leicester, England. The method builds a 3-D model from the design, layer by layer, by sintering polymeric powders specifically selected for the new process, according to the statement.

The resulting customized helmets are made of the same amount of expanded polystyrene as is used in standard and certified helmets, according to the statement. The material acts as the helmet's shock absorber.

The project has already produced five customized helmets. Riders will next perform long-ride tests to verify improvement in comfort. Project members will also evaluate and record other issues, such as noise levels and airflow.

IMSI Design of Novato, Calif., has released IDX ToleranceCalc version five, a one- and two-dimensional tolerance analysis solution that works with drawing-exchange-file CAD applications.

MecSoft Corp. of Irvine, Calif., has released VisualMill 6.0 Professional, which introduces three-axis toolpath generation methods to the VisualMill product suite.

Atalasoft Inc. of Boston, which makes imaging components for Microsoft.NET Framework-based developers, has released DotImage 6.0, the latest version of its Imaging Toolkit.

A maker of physics-based simulation software, ESI Group of Chicago, has released an upgrade to its PAM-CEM Solutions software package. This product allows users to perform predictive electromagnetic compatibility simulations.

Mechdyne Corp. of Marshalltown, Iowa, has released an upgrade to its professional application programmer interface and library for development of interactive three-dimensional environments. The new release, CaveLib Version 3.2, adds support for 64-bit operating systems on the x86 architecture.

Granta Design of Cambridge, England, is shipping Granta MI version 2.0, for materials information management in industries including aerospace, defense, energy, automotive, consumer products, and industrial equipment.

Spicer Corp. of Kitchener, Ontario, which makes viewing, redaction, and scanning software, has released ViewCafe 4.2, with online review and collaboration capabilities.

Dynasim of Bielefeld, Germany, has released Dymola 7.0, the latest version of the company's object-oriented modeling and simulation tool.

Creaform of Levis, Quebec, is now shipping the second version of VxScan, its data acquisition software for the company's Handyscan 3-D line of scanners.

Robert McNeel & Associates of Seattle, which makes surfacing software, and SpaceClaim of Concord, Mass., which makes 3-D design software, announced an integration between Rhinoceros and SpaceClaim LTX. The integration allows users to open Rhino files directly in SpaceClaim LTX in order to create solid geometry.

Siemens PLM Software of Plano, Texas, and IT service provider Wipro Technologies of Bangalore, India, have announced a global consulting and systems integrator alliance to provide optimized PLM software and services to customers.

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