Quantum Stripe Search

by Jan Zaanen Nature, 27 Apr 2006 Do quantum stripes exist or not? Further indirect evidence for this controversial behaviour of electrons in high-temperature superconductors comes from measurements of atomic-lattice vibrations. Read more

Wave and Defect Dynamics in Nonlinear Photonic Quasicrystals

by Barak Freedman et al. Nature, 27 Apr 2006 Quasicrystals are unique structures with long-range order but no periodicity. Their properties have intrigued scientists ever since their discovery and initial theoretical analysis. The lack of periodicity excludes the possibility of describing quasicrystal structures with well-established analytical tools, including common notions like Brillouin zones and Bloch's theorem. New and unique features such as fractal-like band structures and 'phason' degrees of freedom are introduced. In general, it is very difficult to directly observe the evolution of electronic waves in solid-state atomic quasicrystals, or the dynamics of the structure itself. Here we use optical induction to create two-dimensional photonic quasicrystals, whose macroscopic nature allows us to explore wave transport phenomena. We demonstrate that light launched at different quasicrystal sites travels through the lattice in a way equivalent to quantum tunnelling of electrons in a quasiperiodic potential. At high intensity, lattice solitons are formed. Finally, we directly observe dislocation dynamics when crystal sites are allowed to interact with each other. Our experimental results apply not only to photonics, but also to other quasiperiodic systems such as matter waves in quasiperiodic traps, generic pattern-forming systems as in parametrically excited surface waves, liquid quasicrystals, and the more familiar atomic quasicrystals. Read more

Dual Properties of Carbon Nanotubes Revealed

PhysOrg.com, 28 Apr 2006 For the first time, researchers have directly measured the electronic structure of individual carbon nanotubes whose physical properties had already been determined. This new study, pioneered by researchers at the U.S. Department of Energy’s Brookhaven National Laboratory working with their colleagues at Columbia University, may help scientists determine the usefulness of carbon nanotubes in various applications, from microelectronics to mechanical, thermal, and photovoltaic devices. Read more

Ferroelectric Phase Transition in Individual Single-Crystalline BaTiO3 Nanowires

by Jonathan E. Spanier et al. Nano Letters, 15 Mar 2006 (web release) We report scanned probe characterizations of the ferroelectric phase transition in individual barium titanate nanowires. Variable-temperature electrostatic force microscopy is used to manipulate, image, and evaluate the diameter-dependent stability of ferroelectric polarizations. These measurements show that the ferroelectric phase transition temperature (TC) is depressed as the nanowire diameter (dnw) decreases, following a 1/dnw scaling. The diameter at which TC falls below room temperature is determined to be ~3 nm, and extrapolation of the data indicates that nanowires with dnw as small as 0.8 nm can support ferroelectricity at lower temperatures. We also present density functional theory calculations of bare and molecule-covered barium titanate surfaces. These calculations indicate that ferroelectricity in nanowires is stabilized by molecular adsorbates such as OH and carboxylates. These adsorbates are found to passivate polarization charge more effectively than metallic electrodes, explaining the observed stability of ferroelectricity in small-diameter barium titanate nanowires. Read more

Micro-Pump Is Cool Idea for Future Computer Chips

Purdue University Public Release, 26 Apr 2006 Engineers at Purdue University have developed a tiny "micro-pump" cooling device small enough to fit on a computer chip that circulates coolant through channels etched into the chip. Read more

Dislocation Multi-Junctions and Strain Hardening

by Vasily V. Bulatov Nature, 27 Apr 2006 At the microscopic scale, the strength of a crystal derives from the motion, multiplication and interaction of distinctive line defects called dislocations. First proposed theoretically in 1934 to explain low magnitudes of crystal strength observed experimentally, the existence of dislocations was confirmed two decades later. Much of the research in dislocation physics has since focused on dislocation interactions and their role in strain hardening, a common phenomenon in which continued deformation increases a crystal's strength. The existing theory relates strain hardening to pair-wise dislocation reactions in which two intersecting dislocations form junctions that tie the dislocations together. Here we report that interactions among three dislocations result in the formation of unusual elements of dislocation network topology, termed 'multi-junctions'. We first predict the existence of multi-junctions using dislocation dynamics and atomistic simulations and then confirm their existence by transmission electron microscopy experiments in single-crystal molybdenum. In large-scale dislocation dynamics simulations, multi-junctions present very strong, nearly indestructible, obstacles to dislocation motion and furnish new sources for dislocation multiplication, thereby playing an essential role in the evolution of dislocation microstructure and strength of deforming crystals. Simulation analyses conclude that multi-junctions are responsible for the strong orientation dependence of strain hardening in body-centred cubic crystals. Read more

Researchers Create Biologically-Inspired Artificial Compound Eye

University of California - Berkeley Public Release, 27 Apr 2006 Using the eyes of insects such as dragonflies and houseflies as models, a team of bioengineers at University of California, Berkeley, has created a series of artificial compound eyes. Read more

Carnegie Mellon Unveils Futuristic Unmanned Ground Combat Vehicles

Carnegie Mellon University Public Release, 28 Apr 2006 Carnegie Mellon University's National Robotics Engineering Center in the School of Computer Science's Robotics Institute is unveiling a unique unmanned ground vehicle that offers new strength, mobility and autonomy features for the Army's effort to keep its troops out of harm's way. Read more

A Biosensor Layered Like Lasagna

DOE/Pacific Northwest National Laboratory Public Release, 28 Apr 2006 In a mixing of pasta metaphors, Pacific Northwest National Laboratory scientists have used electrostatic attraction to layer reactive biological molecules lasagna-like around spaghetti-like carbon nanotubes. Read more

Excitation of Surface Dipole and Solenoidal Modes on Toroidal Structures

by M. Encinosa & M. Jack arXiv.org E-print Archive, 27 Apr 2006 The time dependent Schrodinger equation inclusive of curvature effects is developed for a spinless electron constrained to motion on a toroidal surface and subjected to circularly polarized and linearly polarized waves in the microwave regime. A basis set expansion is used to determine the character of the surface currents as the system is driven at a particular resonance frequency. Surface current densities and magnetic moments corresponding to those currents are calculated. It is shown that the currents can yield magnetic moments large not only along the toroidal symmetry axis, but along directions tangential and normal to the toroidal surface as well. Read more

Enhancing the Photomixing Efficiency of Optoelectronic Devices in the Terahertz Regime

by Subrahmanyam Pilla arXiv.org E-print Archive, 27 Apr 2006 A method to reduce the transit time of majority of carriers in photomixers and photo detectors is proposed. Enhanced optical fields associated with surface plasmon polaritons, coupled with velocity overshoot phenomenon results in net decrease of transit time of carriers. As an example, model calculations demonstrating improvement in THz power generation efficiency of a photomixer based on Low Temperature grown GaAs are presented. Due to minimal dependence on the carrier recombination time, it is anticipated that the proposed method paves the way for enhancing the speed and efficiency of photomixers and detectors covering UV to far infrared communications wavelengths. Read more

Heat Transfer in Theory of Relativity

by A. Brotas & J. C. Fernandes arXiv.org E-print Archive, 27 Apr 2006 The traditional Fourier equation just allows us to study the evolution of temperature in an "undeformable" bar. The search for its relativistic variant is a task which is expected to fail because in relativity there are no undeformable bars. Rigid bodies, in the sense of "as rigid as possible," are deformables. In this work we show how to write in relativity the system of equations necessary to study simultaneously deformation and temperature evolution along a rigid deformable bar. The solutions of the two simultaneous equations is discussed assuming convenient constitutive relations for the material. An application is presented. Read more

Tritium Locked in Silica Using 248 nm KrF Laser Irradiation

by Baojun Liu & Kevin P. Chen Applied Physics Letters, 27 Mar 2006 In this Letter we report on selectively occluding tritium in a silica film on a silicon substrate using a combination of high-pressure tritium loading and 248nm KrF laser irradiation. Sixty percent of tritium dissolved in the silica film was bonded by laser irradiation. The concentration of the bonded tritium was proportional to the total laser fluence. Tritium effusion experiments indicated that the laser-locked tritium existed stably in the glass matrix up to 400° C. In this work we point a way to a safe and simple approach for the integration of on-chip radioisotope micropower sources for micromechanical and microelectronic applications. Read more

'Green Roofs' Growing More Popular

CNN.com, 28 Apr 2006 An architectural organization has unveiled a new "green" roof for its own building to showcase a trend toward environmentally-friendly technology. The leafy rooftop of the American Society of Landscape Architects building in downtown Washington is a model of the techniques used increasingly to cool temperatures, filter air, and lessen the burden on sewers by absorbing rainwater. Read more

Experimental Synchronization of Independent Entangled Photon Sources

by Tao Yang et al. Physical Review Letters, 20 Mar 2006 We report the generation of independent entangled photon pairs from two synchronized but mutually incoherent laser sources. The quality of synchronization is confirmed by observing a violation of Bell's inequality with 3.2 standard deviations in an entanglement swapping experiment. The techniques developed in our experiment are not only important for realistic linear optical quantum-information processing, but also enable new tests of local realism. Read more

More Cash for the Labs?

by Cameron Crotty Electronic Business, 1 Apr 2006 If the rest of the year plays out as well as it started, 2006 might become known as the year the electronics industry finally got traction in Washington, D.C. At his State of the Union address in January, President Bush announced his American Competitiveness Initiative (ACI). The ACI part of the presidential budget, proposes that -- among other things -- the U.S. government double its investment in basic research in the physical sciences over the next 10 years. Read more

The New Breed of Soldier: Robots with Guns

by Steven Komarow USA TODAY, 14 Apr 2006 Spurred by the risks from roadside bombs and terrorist ambushes, the military is aggressively seeking to replace troops with battlefield robots, including new versions armed with machine guns. Read more

Catalytic Alkane Metathesis by Tandem Alkane Dehydrogenation-Olefin Metathesis

by Alan S. Goldman et al. Science, 14 Apr 2006 With petroleum supplies dwindling, there is increasing interest in selective methods for transforming other carbon feedstocks into hydrocarbons suitable for transportation fuel. We report the development of highly productive, well-defined, tandem catalytic systems for the metathesis of n-alkanes. Each system comprises one molecular catalyst that effects alkane dehydrogenation and olefin hydrogenation, plus a second catalyst for olefin metathesis. The systems all show complete selectivity for linear product. We report one example that achieves selectivity with respect to the distribution of product molecular weights, in which n-decane is the predominant high-molecular-weight product of the metathesis of two moles of n-hexane. Read more

Scientists Probe the Use of the Tongue

by Melissa Nelson USATODAY.com, 24 Apr 2006 In their quest to create the super warrior of the future, some military researchers aren't focusing on organs like muscles or hearts. They're looking at tongues. By routing signals from helmet-mounted cameras, sonar and other equipment through the tongue to the brain, they hope to give elite soldiers superhuman senses similar to owls, snakes and fish. Researchers at the Florida Institute for Human and Machine Cognition envision their work giving Army Rangers 360-degree unobstructed vision at night and allowing Navy SEALs to sense sonar in their heads while maintaining normal vision underwater -- turning sci-fi into reality. Read more

Exploring Complex Networks through Random Walks

by Luciano da Fontoura Costa arXiv.org E-print Archive, 24 Apr 2006 Most real complex networks -- such as protein interactions, social contacts, the internet -- are only partially known and available to us. While the process of exploring such networks in many cases resembles a random walk, it becomes a key issue to investigate and characterize how effectively the nodes and edges of such networks can be covered by different strategies. At the same time, it is critically important to infer how well can topological measurements such as the average node degree and average clustering coefficient be estimated during such network explorations. The present article addresses these problems by considering random and Barab\'asi-Albert (BA) network models with varying connectivity explored by three types of random walks: traditional, preferential to untracked edges, and preferential to unvisited nodes. A series of relevant results are obtained, including the fact that random and BA models with the same size and average node degree allow similar node and edge coverage efficiency, the identification of linear scaling with the size of the network of the random walk step at which a given percentage of the nodes/edges is covered, and the critical result that the estimation of the averaged node degree and clustering coefficient by random walks on BA networks often leads to heavily biased results. Many are the theoretical and practical implications of such results. Read more

Interplay between Function and Structure in Complex Networks

by Timothy C. Jarrett et al. arXiv.org E-print Archive, 21 Apr 2006 We show that abrupt structural transitions can arise in functionally optimal networks, driven by small changes in the level of transport congestion. Our results offer an explanation as to why so many diverse species of network structure arise in Nature under essentially the same environmental conditions. Our findings are based on an exactly solvable model system which mimics a variety of biological and social networks. We then extend our analysis by introducing a novel renormalization scheme involving cost motifs, to describe analytically the average shortest path across multiple-ring-and-hub networks. As a consequence, we uncover a 'skin effect' whereby the structure of the inner multi-ring core can cease to play any role in terms of determining the average shortest path across the network. Read more

Caught by the Sound of Your Speeding Car

by Barry Fox New Scientist, 24 Apr 2006 A hidden trap that detects how fast vehicles are going just by listening to them as they pass could catch speeding drivers unawares. The system, being developed by the University of Tennessee and the Battelle Institute in Oak Ridge, uses microphones hidden by the roadside to measure the speed of passing vehicles. It does not emit tell-tale radiation, unlike radar or laser-based devices, so it cannot be picked up by dashboard detectors. Read more

Bio Fuel Cells Could Power Portable Gadgets

by Tom Simonite NewScientist.com, 21 Apr 2006 A hydrogen fuel cell that uses enzymes instead of expensive metal catalysts to drive chemical reactions has been developed by UK researchers. Enzyme-powered fuel cells could be smaller, simpler and cheaper to make than conventional ones, the researchers claim. Read more

Solar-Powered Implant Could Restore Vision

by Celeste Biever New Scientist, 23 Apr 2006 An implant that squirts chemicals into the back of your eye may not sound like much fun. But a solar-powered chip that stimulates retinal cells by spraying them with neurotransmitters could restore sight to blind people. Read more

Robo-Turtle Answers Some Flippery Questions

by Tom Simonite NewScientist.com, 24 Apr 2006 A robotic turtle could help engineers build better autonomous underwater vehicles and answer fundamental questions about how prehistoric beasts swam. The robot, called Madeleine, is already helping researchers understand when it is best to swim with four flippers and when to use two. Read more

Innovation: Pick of the Latest Patent Applications

by Tami Freeman fibers.org News, 19 Apr 2006

• Polymer waveguide eases optical links
• FTTP scheme relies upon modulation, multiplexing
• Novel optical cable stops the water from getting in
• Restricted modes enable low-cost radio-over-fibre
• Satellite and cable signals travel over optical network
• Photonic crystal designed with high refractive index
• Hybrid protection keeps optical networks running
• Connector design allows accurate on-site splicing
• Encrypted signals ensure secure data transmission

Read more

Networks: An Automated Future?

fibers.org News, 24 Apr 2006 It's 40 years since the concept of transmitting information via light signals through glass was first formally proposed. Scientists at UK-based Standard Telecommunication Laboratories published a paper describing the guiding of light along an optical fibre and cited the technique as having "important potential as a new form of communication medium." A lot has changed since the first demonstration of communication over optical fibre. Nowadays, it's cost, not speed, that's driving the new technology breakthroughs. Read more

Optimising Control of Wind Generators

Basque Research Public Release, 24 Apr 2006 The School of Engineering at Bayonne is working on a research project on control optimisation for the latest-generation wind generators using intelligent microsensors. The latest-generation wind generators work at variable speed and with pitch regulation based on the pitch angle of the rotor blades. These degrees of freedom enable an increase in energy yield, a decrease in fatigue due to mechanical loads and an enhancement in the quality of the electrical potential with respect to fixed-speed wind turbines. The rotation speed and the pitch angle of the blades are controlled continuously by control algorithms and the quality of these algorithms have a determining influence on the price of the energy produced by the wind generators. Although a large amount of research work on wind generator control has been undertaken, it still remains for more "intelligence" to be introduced into their functioning. Read more

Scientists Devise Means to Test for Phony Technical Papers

Public Release, 24 Apr 2006 Indiana University Authors of bogus technical articles beware. A team of researchers at the Indiana University School of Informatics has designed a tool that distinguishes between real and fake papers. It's called the Inauthentic Paper Detector -- one of the first of its kind anywhere -- and it uses compression to determine whether technical texts are generated by man or machine. Read more

Truck Stop Electrification Stations

Department of Energy/National Renewable Energy Laboratory Public Release, 24 Apr 2006 A new internet-based mapping program is helping truckers find truck stops with idle reduction facilities -- on-site systems that can substantially cut fuel use while reducing air emissions. Idle reduction systems hold great promise for the approximately 500,000 long-haul trucks with sleeper cabs currently operating in the United States. Estimates show idle reduction technologies could reduce diesel fuel use by about 800 million gallons annually. In addition, idle reduction strategies can reduce NOX emissions by approximately 150,000 tonnes per year and particulate matter emissions by up to 3,000 tonnes per year. By reducing the amount of time that trucks idle, typically 6 hours per night, drivers can significantly reduce engine wear and associated maintenance costs. Routine maintenance can be performed less often and trucks can travel farther before needing an engine overhaul. Read more

Snake Robots Could Aid in Rescues

CNN News, 12 Apr 2006 For most people, snakes seem unpleasant or even threatening. But Howie Choset sees in their delicate movements a way to save lives. The 37-year-old Carnegie Mellon University professor has spent years developing snakelike robots he hopes will eventually slither through collapsed buildings in search of victims trapped after natural disasters or other emergencies. Read more

Green Mini-Car to Beat Congestion

by Jonathan Fildes BBC News, 24 Apr 2006 A tiny, three-wheeled car that could help solve city congestion has been demonstrated at the University of Bath. The prototype CLEVER (Compact Low Emission Vehicle for Urban Transport) car is one metre wide and less polluting than normal vehicles. Read more

Electrostatic Self-Assembly of Binary Nanoparticle Crystals with a Diamond-Like Lattice

by Alexander M. Kalsin et al. Science 21, Apr 2006 Self-assembly of charged, equally sized metal nanoparticles of two types (gold and silver) leads to the formation of large, sphalerite (diamond-like) crystals, in which each nanoparticle has four oppositely charged neighbors. Formation of these non-close-packed structures is a consequence of electrostatic effects specific to the nanoscale, where the thickness of the screening layer is commensurate with the dimensions of the assembling objects. Because of electrostatic stabilization of larger crystallizing particles by smaller ones, better-quality crystals can be obtained from more polydisperse nanoparticle solutions. Read more

Atomic Pillar-Based Nanoprecipitates Strengthen AlMgSi Alloys

by J. H. Chen et al. Science 21, Apr 2006 Atomic-resolution electron microscopy reveals that pillarlike silicon double columns exist in the hardening nanoprecipitates of AlMgSi alloys, which vary in structure and composition. Upon annealing, the Si₂ pillars provide the skeleton for the nanoparticles to evolve in composition, structure, and morphology. We show that they begin as tiny nuclei with a composition close to Mg₂Si₂Al₇ and a minimal mismatch with the aluminum matrix. They subsequently undergo a one-dimensional growth in association with compositional change, becoming elongated particles. During the evolution toward the final Mg₅Si₆ particles, the compositional change is accompanied by a characteristic structural change. Our study explains the nanoscopic reasons that the alloys make excellent automotive materials. Read more

Bolometric Infrared Photoresponse of Suspended Single-Walled Carbon Nanotube Films

by Mikhail E. Itkis et al. Science, 21 Apr 2006 The photoresponse in the electrical conductivity of a single-walled carbon nanotube (SWNT) film is dramatically enhanced when the nanotube film is suspended in vacuum. We show here that the change in conductivity is bolometric (caused by heating of the SWNT network). Electron-phonon interactions lead to ultrafast relaxation of the photoexcited carriers, and the energy of the incident infrared radiation (IR) is efficiently transferred to the crystal lattice. It is not the presence of photoexcited holes and electrons, but a rise in temperature, that results in a change in resistance; thus, photoconductivity experiments cannot be used to support the band picture over the exciton model of excited states in carbon nanotubes. The photoresponse of suspended SWNT films is sufficiently high that they may function as the sensitive element of an IR bolometric detector. Read more

Office of Naval Research Funding Opportunity - Electronics Technology

The goal of the electronics program is to develop and transition affordable, high performance Radio Frequency (RF) electronics that will provide a decisive edge to the warfighter. The program encompasses RF research, design, modeling, fabrication, and testing of devices, integrated circuits, and multi-chip assemblies that span digital, analog, microwave and millimeter wave technologies. Toward that end the Electronics Science and Technology Program invests in science and technology initiatives that will provide the present Navy, the Next Navy, and Navy After Next with electronics technology to meet these needs. Read more

Brain Cells Fused with Computer Chip

by Ker Than LiveScience, 27 Mar 2006 The line between living organisms and machines has just become a whole lot blurrier. European researchers have developed "neuro-chips" in which living brain cells and silicon circuits are coupled together. The achievement could one day enable the creation of sophisticated neural prostheses to treat neurological disorders or the development of organic computers that crunch numbers using living neurons. Read more

New Process Builds Electronic Function Into Optical Fiber

ScienceDaily, 27 Mar 2006 Optical fiber helped bring us the Internet, and silicon/germanium devices brought us microelectronics. Now, a joint team from Penn State University and the University of Southampton has developed a new way to combine these technologies. The team has made semiconductor devices, including a transistor, inside microstructured optical fibers. The resulting ability to generate and manipulate signals inside optical fibers could have applications in fields as diverse as medicine, computing, and remote sensing devices. Read more

New Research Aims to Plug Holes in VOIP before They Happen

PhysOrg.com, 4 Apr 2006 The National Science Foundation has issed four awards totaling $600,000 to the University of North Texas to lead a multi-university collaboration to develop a geographically distributed, secure test bed to analyze vulnerabilities in Voice over Internet Protocol -- an increasingly popular technology that turns audio signals into digital data that can be transmitted over the Internet. Read more

Optical Image Correlation in Photorefractive Mesogenic Composites

by Akira Emoto, Hiroshi Ono, & Nobuhiro Kawatsuki AZojomo, 2 Mar 2006 We demonstrated optical image correlation by means of Fourier transform hologram in the region of Raman-Nath diffraction on to photorefractive mesogenic composites film. Interference field of two Fourier-transformed imaging beams induce periodically molecular reorientation: holographic phase gratings. The reconstructed image is obtained as a result of a spatial correlation between the two optical images. In this work we applied correlation output between two optical images for pattern classification and/or detection according to the self-diffraction. The proposed optical correlation was confirmed with an example of a pattern in the experiments. Read more

Military Users Giving Second Thoughts to Ruggedized Laptops

by John Keller Military & Aerospace Electronics, March 2006 U.S. manufacturers of rugged laptop and notebook computers have a message for the U.S. Department of Defense (DOD), which is deploying forces in increasing numbers that need reliable and lightweight computing power: "We told you so." That’s right. No so long ago plenty of DOD officials could be found who said ruggedized laptop computers were largely unnecessary for all except the most extreme of operating environments. Dust, direct sunlight, some moisture here and there -- not a big deal. If a notebook computer failed in the field, so what? These machines are cheap enough to make simply throwing away the bad computer and replacing it with a new one a viable option. At least that’s what they thought. Read more

Med Students Train on Robots

Associated Press Wired News, 16 Apr 2006 Noelle's given birth in Afghanistan, California and dozens of points in between. She's a lifelike, pregnant robot used in increasing numbers of medical schools and hospital maternity wards. The full-sized, blond, pale mannequin is in demand because medicine is rapidly abandoning centuries-old training methods that use patients as guinea pigs, turning instead to high-tech simulations. It's better to make a mistake on a $20,000 robot than a live patient. Read more

When an Algorithm Takes the Wheel

by Bruce Gain Wired News, 17 Apr 2006 Algorithmically controlled sensors, suspension adjustment and other electronic functions are not what you are supposed to notice when you drive Jaguar's new XK convertible and coupe. The car's highly automated driving control, Jaguar engineers say, is supposed to transparently keep you out of trouble -- while you embark upon a high-powered sport car driving experience. Read more

Symmetry-, Time-, and Temperature-Dependent Strength of Carbon Nanotubes

by Traian Dumitrica, Ming Hua, & Boris I. Yakobson Proceedings of the National Academy of Sciences, 18 Apr 2006 Although the strength of carbon nanotubes has been of great interest, their ideal value has remained elusive both experimentally and theoretically. Here, we present a comprehensive analysis of underlying atomic mechanisms and evaluate the yield strain for arbitrary nanotubes at realistic conditions. For this purpose, we combine detailed quantum mechanical computations of failure nucleation and transition-state barriers with the probabilistic approach of the rate theory. The numerical results are then summarized in a concise set of equations for the breaking strain. We reveal a competition between two alternative routes of brittle bond breaking and plastic relaxation, determine the domains of their dominance, and map the nanotube strength as a function of chiral symmetry, tensile test time, and temperature. Read more

Large Eddy Approximation of Turbulent Flow in DSC Schemes

by Steffen Hein arXiv.org E-print Archive, 15 Apr 2006 Large eddy approximation of turbulent flow is given a natural setting in the DSC framework of computational fluid dynamics. Periodic cellular coarse-graining prevents the nodal flow from piling up and preserves its large patterns. The coarsening operations are consistent with the near-field interaction principle of DSC and -- therefore -- uncomplicated at boundaries. Numerical examples validate the approach. Read more

Optical Properties of Star-Shaped Gold Nanoparticles

by Colleen L. Nehl, Hongwei Liao, & Jason H. Hafner Nano Letters, 28 Mar 2006 (web release) Here we report the synthesis, structure, and optical properties of ca. 100 nm star-shaped gold nanoparticles. Single particle spectroscopy measurements revealed that these nanoparticles have multiple plasmon resonances resulting in polarization-dependent scattering with multiple spectral peaks, which correspond to the different tips on the star-shaped structure. The plasmon resonances were also found to be extremely sensitive to the local dielectric environment. Read more

When Photons Go AWOL

by Mark Anderson New Scientist, 15 Apr 2006 James Franson is no stranger to strange things. He has done plenty of experiments showing, for example, that quantum entanglement really is as spooky as it seems. Einstein hated the idea, but Franson has seen at first hand that two quantum particles, such as photons, can affect each other's properties no matter how far apart they might be. Even that degree of experience in negotiating quantum weirdness, however, did not prepare Franson for what he has just found. It turns out that it is not just quantum particles that get entangled: if Franson's calculations are correct, you can entangle bits of empty space as well. Einstein would really have been spooked by this one. Read more

Predicting Severe Head Injury after Light Motor Vehicle Crashes

by Daniel Talmor Accident Analysis & Prevention (article in press) Motor vehicle crashes (MVC) are a leading public health problem. Improving notification times and the ability to predict which crashes will involve severe injuries may improve trauma system utilization. This study was undertaken to develop and validate a model to predict severe head injury following MVC using information readily incorporated into an automatic crash notification system. We have developed a prediction model for head injury in MVC. As the development of automatic crash notification systems improves, models such as this one will be necessary to permit triage of what would be an overwhelming increase in crash notifications to pre-hospital responders. Read more

Nano-Car Gets an Engine

by Tom Simonite NewScientist.com, 14 Apr 2006 Researchers have installed a molecular engine into a "car" just a few billionths of a metre long. Measuring just 3 by 4 nanometres, around 20,000 of the cars could be parked on the tip of a human hair. Read more

Resonant-Cavity LEDs Fire Up In-Car Networks

by John Lambkin fibers.org News, 5 Apr 2006 Today's car owners are demanding more from their vehicles than just good looks. They now want models offering greater levels of comfort, safety, fuel efficiency and reliability, along with features such as in-car navigation systems, GPS telephones, satellite radios, DVD players and Internet browsing facilities. All of these features are implemented through the car's infotainment bus, which is a network of digital electronic devices operating at high data rates in an extremely harsh and electromagnetically noisy environment. The plastic optical fiber networks that feature in many of today's cars have data transmission rates that are limited by LED switching speeds. This barrier can be overcome, though, if these light sources are replaced with resonant-cavity LEDs. Read more

Carrier Ethernet: Set for Mass Market Adoption?

by Fred Ellefson fibers.org News, 18 Apr 2006 A carrier's ability to remotely manage Ethernet networks and services is key to controlling operational expense and avoiding costly visits to customer sites. Carriers are accustomed to the operation, administration and maintenance (OAM) capabilities inherent in the SDH/SONET technology that forms the foundation of their legacy infrastructure. In the Ethernet space, however, they remain sceptical about the ability to remotely monitor and manage a network via Ethernet OAM. But in the coming year, carriers' eyes will be opened to a more intelligent Ethernet service, with sophisticated OAM functionality that addresses this opex challenge. Read more

New Student-Designed System Tracks Firefighters, Special Forces

University of Florida Public Release, 13 Apr 2006 The old technique of using push pins and maps to track troop movements just got a radical new upgrade for soldiers or firefighters in rugged terrains. A group of University of Florida engineering students has designed a system to locate, track and communicate with special forces troops or firefighters in remote areas where no cell towers or other communications infrastructure exist. Read more

Microfluidic Device Tests Fluid Compatibility

National Institute of Standards and Technology Public Release, 14 Apr 2006 The key to a great party is inviting guests who mix well and don't instill tension among their fellow revelers. The key to a great detergent, cosmetic, paint or other complex liquid product is pretty much the same -- include components that mix well and don't have high levels of what scientists call "interfacial tension," a tendency to bead up and pull away from each other. To help industrial engineers improve their ability to systematically test new product formulations, researchers at the National Institute of Standards and Technology have developed a microfluidic instrument that quickly measures interfacial tension. Read more

A Solution-Processed 1.53 μm Quantum Dot Laser with Temperature-Invariant Emission Wavelength

by S. Hoogland et al. Optics Letters, 17 Apr 2006 Sources of coherent, monochromatic short-wavelength infrared light are essential in telecommunications, biomedical diagnosis, and optical sensing. Today’s semiconductor lasers are made by epitaxial growth on a lattice-matched single-crystal substrate. This strategy is incompatible with integration on silicon. Colloidal quantum dots grown in solution can, in contrast, be coated onto any surface. Here we show a 1.53 μm laser fabricated using a remarkably simple process: dipping a glass capillary into a colloidal suspension of semiconductor quantum dots. We developed the procedures to produce a smooth, low-scattering-loss film inside the capillary, resulting in a whispering gallery mode laser with a well-defined threshold. While there exist three prior reports of optical gain in infrared-emitting colloidal quantum dots, this work represents the first report of an infrared laser made using solution processing. We also report dλmax/dT, the temperature-sensitivity of lasing wavelength, of 0.03 nm/K, the lowest ever reported in a colloidal quantum dot system and 10 times lower than in traditional semiconductor quantum wells. Read more

Polluted Ground Water Poured into a Model

Netherlands Organization for Scientific Research Public Release, 14 Apr 2006 Dutch researcher Phil Ham has developed mathematical models to calculate the natural degradation capacity of polluted groundwater. As a result of this, it can now be predicted whether a polluted area will become larger or smaller. In the latter case, expensive remediation methods can be avoided. Read more

Management of Singlet and Triplet Excitons for Efficient White Organic LEDs

by Yiru Sun et al. Nature, 13 Apr 2006 Lighting accounts for approximately 22 per cent of the electricity consumed in buildings in the United States, with 40 per cent of that amount consumed by inefficient (approx15 lm W^-1) incandescent lamps. This has generated increased interest in the use of white electroluminescent organic light-emitting devices, owing to their potential for significantly improved efficiency over incandescent sources combined with low-cost, high-throughput manufacturability. The most impressive characteristics of such devices reported to date have been achieved in all-phosphor-doped devices, which have the potential for 100 per cent internal quantum efficiency: the phosphorescent molecules harness the triplet excitons that constitute three-quarters of the bound electron-hole pairs that form during charge injection, and which (unlike the remaining singlet excitons) would otherwise recombine non-radiatively. Here we introduce a different device concept that exploits a blue fluorescent molecule in exchange for a phosphorescent dopant, in combination with green and red phosphor dopants, to yield high power efficiency and stable colour balance, while maintaining the potential for unity internal quantum efficiency. Two distinct modes of energy transfer within this device serve to channel nearly all of the triplet energy to the phosphorescent dopants, retaining the singlet energy exclusively on the blue fluorescent dopant. Additionally, eliminating the exchange energy loss to the blue fluorophore allows for roughly 20 per cent increased power efficiency compared to a fully phosphorescent device. Our device challenges incandescent sources by exhibiting total external quantum and power efficiencies that peak at 18.7 0.5% and 37.6 0.6 lm W^-1, respectively, decreasing to 18.4 0.5% and 23.8 0.5 lm W^-1 at a high luminance of 500 cd m^-2. Read more

Robotic Footballers Have a Ball

by Jonathan Fildes BBC News, 14 Apr 2006 A football tournament between teams of robots has been won by students from Plymouth University. The third robot football UK championships ended in defeat for organisers Warwick University. The event was aimed at helping the students improve the skills of their robots ahead of the Robot World Cup in Germany in June. The machine shoot-out was held over two days at the Institution of Mechanical Engineers in London. Read more

Double Perovskites as Anode Materials for Solid-Oxide Fuel Cells

Yun-Hui Huang et al. Science, 14 Apr 2006 Extensive efforts to develop a solid-oxide fuel cell for transportation, the bottoming cycle of a power plant, and distributed generation of electric energy are motivated by a need for greater fuel efficiency and reduced air pollution. Barriers to the introduction of hydrogen as the fuel have stimulated interest in developing an anode material that can be used with natural gas under operating temperatures 650°C <>2Mg_1-xMn_xMoO6-{delta} that meet the requirements for long-term stability with tolerance to sulfur and show a superior single-cell performance in hydrogen and methane. Read more

Hardening by Annealing and Softening by Deformation in Nanostructured Metals

Xiaoxu Huang, Niels Hansen, & Nobuhiro Tsuji Science, 14 Apr 2006 We observe that a nanostructured metal can be hardened by annealing and softened when subsequently deformed, which is in contrast to the typical behavior of a metal. Microstructural investigation points to an effect of the structural scale on fundamental mechanisms of dislocation-dislocation and dislocation-interface reactions, such that heat treatment reduces the generation and interaction of dislocations, leading to an increase in strength and a reduction in ductility. A subsequent deformation step may restore the dislocation structure and facilitate the yielding process when the metal is stressed. As a consequence, the strength decreases and the ductility increases. These observations suggest that for materials such as the nanostructured aluminum studied here, deformation should be used as an optimizing procedure instead of annealing. Read more

Piezoelectric Nanogenerators Based on Zinc Oxide Nanowire Arrays

by Zhong Lin Wang & Jinhui Song Science, 14 Apr 2006 We have converted nanoscale mechanical energy into electrical energy by means of piezoelectric zinc oxide nanowire (NW) arrays. The aligned NWs are deflected with a conductive atomic force microscope tip in contact mode. The coupling of piezoelectric and semiconducting properties in zinc oxide creates a strain field and charge separation across the NW as a result of its bending. The rectifying characteristic of the Schottky barrier formed between the metal tip and the NW leads to electrical current generation. The efficiency of the NW-based piezoelectric power generator is estimated to be 17 to 30%. This approach has the potential of converting mechanical, vibrational, and/or hydraulic energy into electricity for powering nanodevices. Read more

Cobalt-Base High-Temperature Alloys

Cobalt-Base High-Temperature Alloys by J. Sato et al. Science, 7 Apr 2006 We have identified cobalt-base superalloys showing a high-temperature strength greater than those of conventional nickel-base superalloys. The cobalt-base alloys are strengthened by a ternary compound with the L1₂ structure, {gamma prime} Co₃(Al,W), which precipitates in the disordered {gamma} face-centered cubic cobalt matrix with high coherency and with high melting points. We also identified a ternary compound, Formula Ir₃(Al,W), with the L1₂ structure, which suggests that the Co-Ir-Al-W–base systems with {gamma + gamma prime} (Co,Ir)₃(Al,W) structures offer great promise as candidates for next-generation high-temperature materials. Read more

Vehicles That Morph for Better Fuel Efficiency

Power Management DesignLine, 27 Mar 2006

Wouldn't it be amazing if an airplane could adjust its wings to catch the changing air currents to improve its fuel efficiency? Well, MIT engineers report they may have found a way for structures -- and materials -- to move in this way, essentially morphing from one shape into another. It could lead to airplanes that morph on demand from one that is energy efficient to one that provides more agility. The material could also be used in boats so their hulls would change shape to be more efficient, no matter the size of the waves.

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Flexible Paper Batteries

Roland Piquepaille's Technology Trends, 27 Mar 2006

For applications that need only small amounts of power, flexible paper batteries look promising by offering a viable alternative to current batteries. These batteries use a paper layer containing the electrolyte as the separator between the anode and the cathode. They are easy and cheap to manufacture because they are produced using printing machines and environmentally friendly because of easy disposal. And as they're thin and flexible, they can be tailored for a large variety of applications, including cosmetics, smart cards, sensors, greeting cards or semi-active RFIDs.

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Plotting the Road Ahead for Wireless Sensor Networks

EU Information Society Technologies Public Release, 27 Mar 2006

Wireless sensor networks are a typical example of a network of 'cooperating objects', tiny embedded computers that cooperate together to produce an intended result. Such embedded systems, be they tiny processors in 'intelligent clothing' or the increasing numbers of computers in automobiles, are characterised by their need to interact with their immediate surroundings. However, it is only by cooperation with other objects that the full capabilities of such networks can be reached.

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Neural Network with Distributed Nodes Provides Fault Tolerance

by James Hereford and Tuze Kuyucu SPIE Newroom, accessed 13 Apr 2006

A system of simple, redundant, interconnected processing nodes forms a neural net that is able to recover when one or more nodes fail.

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Is Optical Quantum Cryptography the 'Holy Grail' of Secure Communication?

by Stamatios Kartalopoulos SPIE Newsroom, accessed 13 Apr 2006

Despite the belief of some researchers, issues exist that mean quantum-optical cryptography may not meet all the demands of secure communication.

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Terahertz's Penetrating Appeal

by Kristin Lewotsky SPIE Professional, April 2006

Imaging at terahertz frequencies offers non-ionizing penetration and spectroscopic capabilities that make it appealing for homeland security, medical, and industrial inspection applications.

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Top 10 Tech Cars

by John Voelcker IEEE Spectrum, April 2006

Nowadays, two technologies are battling for the crown. In one corner stand Japanese and U.S. companies, which have invested billions of dollars in hybrid-electric technology. In the other corner are European makers, with decades of experience in light-duty diesel engines. Today's hybrids cost so much to build that their fuel savings may not cover the higher sticker prices. They are most fuel-efficient in urban, stop-and-go traffic, and least economical at freeway speeds or under hard acceleration. Diesels, on the other hand, tend to be dirty, and some of the air pollution standards they have to meet, such as those in California, are the world's strictest. Yet the will to make a clean diesel is there, because the engines are so fuel-thrifty.

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Engineers Balance Speed and Heat in a Single Board

by Ben Ames Military & Aerospace Electronics, March 2006

Processors and switched-fabric networks are moving data at faster speeds then ever before, which is leading designers to come up with innovative approaches to channeling information flow, power management, and keeping boards cool. Engineers are trying to balance increasing speed and rising heat as they boost the performance of single-board computers. They often use combinations of dedicated processors and field-programmable gate arrays, as well as commercial electronics like the powerful Cell processor and other multi-core integrated circuits.

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Effects of Bottlenecks in Vehicle Traffic

by Syohei Yamamoto, Yasuhiro Hieida & Shin-ichi Tadaki arXiv.org E-print Archive, 10 Apr 2006 Traffic congestion is usually observed at the upper streams of bottlenecks like tunnels. Congestion appears as stop-and-go waves and high density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The emergence of stop-and-go waves depends on the speed reduction in the bottleneck. A phenomenological theory of bottleneck effects is constructed. Read more

A Dynamic Random Access Memory Based on a Conjugated Copolymer

by Qi-Dan Ling Angewandte Chemie (International Edition), 27 Mar 2006 (online) Electroactive organic and polymeric materials are alternatives to traditional Si, Ge, and GaAs semiconductors that have to face the problem of scaling-down in cell size. Several types of organic electronics and devices, including light-emitting diodes, transistors, lasers, photovoltaic cells, switches, and memories, have been realized. Recently, flash (rewritable) memory and write-once read-many-times (WORM) memory based on polymeric materials has been demonstrated. Read more

Switchable Electro-Optic Diffractive Lens with High Efficiency for Ophthalmic Applications

by Guoqiang Li et al. Proceedings of the National Academy of Sciences, 18 Apr 2006 Presbyopia is an age-related loss of accommodation of the human eye that manifests itself as inability to shift focus from distant to near objects. Assuming no refractive error, presbyopes have clear vision of distant objects; they require reading glasses for viewing near objects. Area-divided bifocal lenses are one example of a treatment for this problem. However, the field of view is limited in such eyeglasses, requiring the user to gaze down to accomplish near-vision tasks and in some cases causing dizziness and discomfort. Here, we report on previously undescribed switchable, flat, liquid-crystal diffractive lenses that can adaptively change their focusing power. The operation of these spectacle lenses is based on electrical control of the refractive index of a 5-µm-thick layer of nematic liquid crystal using a circular array of photolithographically defined transparent electrodes. It operates with high transmission, low voltage, fast response, diffraction efficiency > 90%, small aberrations, and a power-failure-safe configuration. These results represent significant advance in state-of-the-art liquid-crystal diffractive lenses for vision care and other applications. They have the potential of revolutionizing the field of presbyopia correction when combined with automatic adjustable focusing power. Read more

Remaking Diesel's Image a Lap at a Time

by Kevin Cameron New York Times, 27 Mar 2006 European roads are bustling with modern diesel cars that do not spew stinky clouds of black smoke from their tailpipes or announce their presence with a truck-stop clatter from under the hood. But with few exceptions, American drivers cannot buy these refined models. Not that it matters. Buyers in the United States do not clamor for these thrifty cars anyway, largely because the diesels they have known were slow, quirky and not worth the fuss so long as gasoline was cheap. But diesels are fast becoming much cooler, and much faster. Read more

Eagle-Cam Provides Aerodynamic Insights

by Will Knight NewScientist.com, 11 Apr 2006 By hitching a ride on an eagle's back, engineers hope to learn how to build aircraft capable of similar feats of aerobatics. In a series of unique experiments, zoologists Graham Taylor and Adrian Thomas at Oxford University have equipped an eagle with miniature spy cameras and other instruments to record its movements during flight in precise detail. The tests have already provided new insight into the way birds control themselves in flight, the pair claim. Read more

The Rough with the Smooth

by Kwing-So Choi Nature, 6 Apr 2006 Those who go with the flow assert that rough surfaces cause turbulence in fluids passing over them. The claim that, under certain conditions, the opposite is possible disturbs that cherished belief. Read more

Solution-Processed Silicon Films and Transistors

by Tatsuya Shimoda Nature, 6 Apr 2006 The use of solution processes -- as opposed to conventional vacuum processes and vapour-phase deposition -- for the fabrication of electronic devices has received considerable attention for a wide range of applications, with a view to reducing processing costs. In particular, the ability to print semiconductor devices using liquid-phase materials could prove essential for some envisaged applications, such as large-area flexible displays. Recent research in this area has largely been focused on organic semiconductors, some of which have mobilities comparable to that of amorphous silicon (a-Si); but issues of reliability remain. Solution processing of metal chalcogenide semiconductors to fabricate stable and high-performance transistors has also been reported. This class of materials is being explored as a possible substitute for silicon, given the complex and expensive manufacturing processes required to fabricate devices from the latter. However, if high-quality silicon films could be prepared by a solution process, this situation might change drastically. Here we demonstrate the solution processing of silicon thin-film transistors (TFTs) using a silane-based liquid precursor. Using this precursor, we have prepared polycrystalline silicon films by both spin-coating and ink-jet printing, from which we fabricate TFTs with mobilities of 108 cm² V^-1 s^-1 and 6.5 cm² V^-1 s^-1, respectively. Although the processing conditions have yet to be optimized, these mobilities are already greater than those that have been achieved in solution-processed organic TFTs, and they exceed those of a-Si TFTs (1 cm² V^-1 s^-1). Read more

Nanobots Found in US Lab

nanotechweb.org News, 1 Apr 2006 Researchers at the University of Petitville, US, have discovered a stache of nanobots in their laboratory. It's thought the structures formed following the accidental exposure of gold-nanoparticle tagged DNA to gamma radiation. Previously considered by many scientists as a work of fiction, the nanobots actually ate through the thesis of nanotechnology PhD student Randall V. Tiny III. "I'm real upset about this," Tiny told nanotechweb.org. "I was just about to hand in my dissertation and the nanobots have totally, like, destroyed it. Looks as if I'm gonna have to get an extension." Tiny has spent the last four years studying the formation of a nanocomposite-based wax for surfboards. "Randall is an excellent student," said lab supervisor Eberhard Sehrklein. "My coworkers say he spends too much time out on the waves but his research has been top quality and the devouring of his thesis is a tragic loss."

Scientists Fashion Semiconductors into Flexible Membranes

University of Wisconsin-Madison Public Release, 9 Apr 2006 University of Wisconsin-Madison researchers have demonstrated a way to release thin membranes of semiconductors from a substrate and transfer them to new surfaces -- an advance that could unite the properties of silicon and many other materials, including diamond, metal and even plastic. Read more

Optimal Distortion-Power Tradeoffs in Sensor Networks: Gauss-Markov Random Processes

by Nan Liu & Sennur Ulukus arXiv.org E-print Archive, 10 Apr 2006 We investigate the optimal performance of dense sensor networks by studying the joint source-channel coding problem. The overall goal of the sensor network is to take measurements from an underlying random process, code and transmit those measurement samples to a collector node in a cooperative multiple access channel with feedback, and reconstruct the entire random process at the collector node. We provide lower and upper bounds for the minimum achievable expected distortion when the underlying random process is stationary and Gaussian. In the case where the random process is also Markovian, we evaluate the lower and upper bounds explicitly and show that they are of the same order for a wide range of sum power constraints. Thus, for a Gauss-Markov random process, under these sum power constraints, we determine the achievability scheme that is order-optimal, and express the minimum achievable expected distortion as a function of the sum power constraint. Read more

On the Low SNR Capacity of Peak-Limited Non-Coherent Fading Channels with Memory

by Amos Lapidoth & Ligong Wang arXiv.org E-print Archive, 7 Apr 2006 The capacity of non-coherent stationary Gaussian fading channels with memory under a peak-power constraint is studied in the asymptotic weak-signal regime. It is assumed that the fading law is known to both transmitter and receiver but that neither is cognizant of the fading realization. A connection is demonstrated between the asymptotic behavior of channel capacity in this regime and the asymptotic behavior of the prediction error incurred in predicting the fading process from very noisy observations of its past. This connection can be viewed as the low signal-to-noise ratio (SNR) analog of recent results by Lapidoth & Moser and by Lapidoth demonstrating connections between the high SNR capacity growth and the noiseless or almost-noiseless prediction error. We distinguish between two families of fading laws: the "slowly forgetting" and the "quickly forgetting." For channels in the former category the low SNR capacity is achieved by IID inputs, whereas in the latter such inputs are typically sub-optimal. Instead, the asymptotic capacity can be approached by inputs with IID phase but block-constant magnitude. Read more

The Next Step for Shipboard Electronics

by Ed Walsh Military & Aerospace Electronics, March 2006 Growth of the U.S. Navy's fleet of surface warships and submarines is riding on systems innovation and new technologies to introduce open-systems solutions for network-centric warfare, ballistic-missile defense, and other capabilities for the 21st century maritime warfare. U.S. Navy leaders are looking at a blend of systems upgrades, technology insertion, and new technology development to help them meet the latest challenges of modern ocean warfare. Leaders are seeking the right technological mix to equip surface ships and submarines for network-centric warfare, cooperative engagement, and sensors integration, while at the same time improving existing platforms to enhance interoperability, affordability, and reliability. Read more

The Next Step for Shipboard Electronics

by Ed Walsh Military & Aerospace Electronics, March 2006 Growth of the U.S. Navy's fleet of surface warships and submarines is riding on systems innovation and new technologies to introduce open-systems solutions for network-centric warfare, ballistic-missile defense, and other capabilities for the 21st century maritime warfare. U.S. Navy leaders are looking at a blend of systems upgrades, technology insertion, and new technology development to help them meet the latest challenges of modern ocean warfare. Leaders are seeking the right technological mix to equip surface ships and submarines for network-centric warfare, cooperative engagement, and sensors integration, while at the same time improving existing platforms to enhance interoperability, affordability, and reliability. Read more

IBM Bakes Security into Processors

by Joris Evers ZDNet News, 9 Apr 2006 Researchers at IBM have come up with a way to hardwire encryption technology into a microprocessor, promising a more secure way to store data. IBM plans to announce availability of the new technology, dubbed Secure Blue, on Monday. IBM envisions its idea and technology will be used in digital media players, electronic organizers, cell phones, computers and devices used by the government and the medical and financial industries. With Secure Blue, data is encrypted and decrypted as it runs through a processor, according to IBM. It is maintained encrypted in the device memory. One of the few times data would not be scrambled is when it is actually displayed. Read more

National Conference on Service Learning in Engineering

The National Science Foundation and the EPICS Program will hold a service learning in engineering conference at the National Academy of Engineering, in Washington, D.C., May 24-25, 2006. There is no charge for registration, but space is limited. If interested, you should sign up at http://epicsnational.ecn.purdue.edu/public/conferences/national_2006_agenda_new.php. An impressive line-up of speakers includes: William Wulf, president of the National Academy of Engineering; Leah H. Jamieson, co-founder of EPICS and president-elect of IEEE; Martin Jischke, president of Purdue University; Wayne Johnson, vice-president of Hewlett Packard; and Sherra Kerns, vice-president for innovation and research at Olin College and ASEE past president.

Boost for UK's Superfast Computer

by Jonathan Fildes BBC News, 2 Apr 2006 Britain's most powerful super computer has received a boost from the government. When it is built in 2007, the high spec number cruncher will be faster than any in Europe. The High-End Computing Terascale Resource, or Hector as it is known, will be owned by the Research Councils of the UK. It will be used by scientists to simulate everything from climate change to atomic structures. The new supercomputer could run at speeds of up to 100 teraflops and will be able to carry out up to 100 trillion calculations every second, 100,000 times faster than an ordinary computer. However, it is unlikely to ever be pushed to its limits, achievable only for short bursts of time that are too small for scientists to run their programs properly. Read more

Mapping Chemicals with Nanoscale Resolution

by Federico Rosei & Fulvio Ratto SPIE Newsroom, accessed 3 Apr 2006 Nanostructured compound materials are attracting increasing interest from scientists in fields as different as physics, materials science, chemistry, and biology. Read more

Quantum-Dot Diodes Provide Sources for Optical Cherence Tomography

by Richard Hogg & Peter Andersen SPIE Newsroom, accessed 3 Apr 2006 Developing low-cost broadband semiconductor IR sources that could enhance the performance and resolution of OCT systems. Read more