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Science & Technology News (843)

Finding Overflow Errors in Software More Effectively

Category: Science & Technology
Posted: March 27, 2015 06:46AM
Author: Guest_Jim_*

Bug testing software can be very difficult and chances are a tester or analyst is going to miss some, so it is understandable that software tools have been developed to aid in the hunt. One of the more common bugs in software is integer overflow, and researchers at MIT have developed a new tool for finding it.

By the nature of computers, there are limits on the data that can be stored, but sometimes a program may exceed that limit. In the case of integers, when that happens the number will just rollover to the beginning, like a car's odometer. In many instances that might not be a serious issue, but sometimes it can be, and many bugs can also be exploited. To hunt them down, the MIT researchers developed Directed Integer Overflow Detection (DIODE) to track a sample input through a program by adding onto its symbolic expression. Even though the sample input will not cause an overflow, DIODE is able to analyze the symbolic expression to determine an input that will. That input is then tested, as checks are likely in place to prevent such inputs, but it will continue until it finds an input that will get through, or concludes an overflow is impossible.

To test DIODE, the researchers ran it and other algorithms on five open-source programs. The other algorithms identified three overflow bugs and DIODE found those three, and 11 more. DIODE does not need the program to be open source though, and can run on the binary of a program, so even a user could run it and report their findings to the developers.

Source: MIT



Password Strength Meters Put to the Test

Category: Science & Technology
Posted: March 26, 2015 02:48PM
Author: Guest_Jim_*

Chances are you have created a password somewhere on the Internet, and there is even a good chance that you were presented with a strength meter of some kind. These are a fairly common tool for encouraging users to create strong passwords by indicating how strong one may be, but just how strong are the meters? Not very, according to researchers at Concordia University, who tested meters for multiple systems, including Google, Yahoo!, Dropbox, Twitter, and Skype, as well as some password managers.

What the researchers found is significant inconsistencies across these services as some would declare a password strong while another would say it is weak. They also found inconsistencies with what was acceptable, as one service may demand multiple character sets be used (letters, numbers, and symbols) while others would be okay just letters. The researchers point out that such weaknesses and inconsistencies can confuse users and make it harder for them to develop actual, stronger passwords. One suggestion the researchers have is to use something at least similar to Dropbox's strength meter, which actually compares passwords against a dictionary and marks any commonly found word as weak, thereby prompting users to be a bit more creative.

The researchers did contact the various companies they tested about their study, but even a year later, significant changes have not been made. Still though, perhaps with this study it may be possible to develop better strength meters for the future.

Source: Concordia University



Heat Used to Breach Air-Gap Security

Category: Science & Technology
Posted: March 25, 2015 02:37PM
Author: Guest_Jim_*

For many organizations, security is of the utmost importance, so they employ tactics such as keeping Internet connected computers separated from those on an internal network. This is called air-gap security, as you keep an air-gap between the two machines. This strategy may not be as secure as some think though, as researchers at Ben-Gurion University of the Negev have developed a piece of malware to cross the gap.

A fact of modern life is that our electronics emit heat as they work, and because too much heat can cause damage, our computers contain sensors. The malware the researchers developed is able to encode digital information into thermal signals that can be detected by a nearby computer's sensors. They call it BitWhisper and it was able to form a bi-directional channel between two computers about 40 cm or 15 inches apart.

As you may have guessed, the system is not necessarily all that fast, but a rate of just eight signals an hour is enough to acquire passwords and secret keys. It is even possible to issue commands using BitWhisper, and no additional hardware or software is required.

 

 

Source: American Associates, Ben-Gurion University of the Negev



Making Quantum Dots from Coal

Category: Science & Technology
Posted: March 25, 2015 06:33AM
Author: Guest_Jim_*

Quantum dots are an interesting technology that could one day find various uses in our devices and be used in solar cells. Before that can happen though, we must find efficient ways to produce them with various properties. Researchers at Rice University have apparently achieved that for graphene oxide dots made from coal.

Quantum dots are semiconducting nanocrystals sometimes called artificial atoms or molecules. This is because they can have some of their properties very precisely tuned, including their optical and semiconducting properties. While large materials will react only with certain frequencies of light, depending on their electronic structure, quantum dots can have that structure tuned to work with any desired frequency. Producing them is so hard though that a kilogram would cost about $1 million. What the Rice researchers have found though brings that down to $100 a ton with two, single-step methods. One of them relies on ultrafiltration to sort the dots by size, a method already used for water filtration, and the other controls the temperature the oxidation process reducing the coal to dots occurs at. The temperature directly influences the size of the dots, which in turn controls the frequencies the dots interact with.

The graphene quantum dots the researchers were working with are photoluminescent, so they emit one color light when light shines on them, and those made from anthracite produced colors from green to orange-red. To produce blue light, the researchers found it easiest to work with bituminous coal. Besides their optical properties and applications, quantum dots could see use in chemical reactions, thanks to their reactive edges.

Source: Rice University



Simple and Scalable Means to Create Graphene Discovered

Category: Science & Technology
Posted: March 24, 2015 01:58PM
Author: Guest_Jim_*

Since its discovery, graphene has been of great interest with its many amazing properties. One issue surrounding the material though has been the challenge to produce it. By a combination of accidental discoveries, researchers at the California Institute of Technology have found a new way to produce graphene that involves one step, and works at room temperature.

The story for the Caltech researchers starts in 2012 when they were trying to grow graphene in a way described in a paper. This method involved heating copper to act as a catalyst, but it was not until the copper was accidentally heated the copper foil for longer than intended that any graphene was made. Then it was realized that the method requires the surface of the copper must be free of copper oxide for it to work. To clean the oxide from the copper, the researchers turned to using hydrogen plasma where another accident led to graphene production. Graphene is a form of carbon, and the source of the carbon in the original method was methane. When working with the hydrogen plasma, methane was leaking from two valves into the area, allowing graphene to grow.

More conventional means of producing graphene involve temperatures as high as 1000 ºC and multiple steps, but this method works at room temperature and is a single step, which should allow it to scale up for large-scale applications. An analysis of the graphene also revealed it to be of very high quality because it does not suffer from heat-induced defects and the graphene grows in lines that form seamless sheets.

Source: California Institute of Technology



Earth May Be a Second Generation Planet

Category: Science & Technology
Posted: March 24, 2015 06:37AM
Author: Guest_Jim_*

As we have developed the instruments to search for planets in other solar systems, we have noticed that there are very few planets like our own. Many are actually what we call super-Earths, which are bigger than Earth but smaller than the gas giant Neptune. Researchers at Caltech have a possible explanation for why our planet is as small as it is, and solves other mysteries too.

Our current understanding of how solar systems form describes a large disc around the star, filled with hydrogen, helium, and objects called planetesimals, which can collect together to form planets. According to the Grand Track scenario, Jupiter formed and was so massive it cleared out part of the disc, and was then being pulled into the Sun, along with the dust and gas in the disc. Saturn then formed and got pulled in towards the Sun as well, but at a faster rate, so it eventually caught up to Jupiter. At this point the two giant planets would achieve orbital resonance and that led to their orbits moving away from the Sun, but not before having disturbed the inner part of the disc. If the Solar System formed like others, and had super-Earths orbiting near the Sun, that disruption could have sent enough of those planetesimals into the super-Earths to cause them to crash into the Sun, destroying them. At this point, much of the gas and dust would have been removed from the inner disc, but if even just a tenth of the planetesimals had achieved circular orbits, there would have been enough mass for the inner planets, Mercury, Venus, Earth, and Mars to form.

Along with explaining why there are no super-Earths here, like we see in other systems, this model also explains why measurements indicate Earth formed 100-200 million years after the Sun had and why there is so little hydrogen in our atmosphere. The hydrogen-filled disc was already gone by the time the second generation of planet formation began in the inner ring.

Source: California Institute of Technology



Helping Light Take Turns

Category: Science & Technology
Posted: March 23, 2015 02:13PM
Author: Guest_Jim_*

Electronics have been serving us well for decades, but we are approaching its limits, unless we develop ways to push the envelope further. One possibility is to use light for transmitting data within computer chips, but this poses a challenge of how to effective control the light on such a small scale. Researchers at the Universities of Central Florida and Texas El Paso have found a solution using nanoscale lattices.

Light likes to travel in a straight line and while a fiber optic cable can make it turn without loss, these turns must be gradual. If the turn is too tight, the light will escape the cable. The lattice the researchers built though, which resembles a honeycomb, is able to turn light without any lose. The researchers made it out of plastic using direct laser writing, which is a nanoscale 3D printing technique.

While this research does represent a record for bending light beams, the researchers are now working to refine the lattice and double the record. As the researchers point out, chances are this technology will enter supercomputers before our favorite devices.

Source: University of Central Florida



Improving Quantum Cryptography with Twisted Light

Category: Science & Technology
Posted: March 23, 2015 06:33AM
Author: Guest_Jim_*

Securing communications is of great importance to many, so a system that is protected from intrusion by the laws of physics is highly desirable. Quantum cryptography is such a system and many are working on various ways to improve the methods of using it. Researchers at the University of Rochester have recently found that using twisted light can improve security even more.

So-called twisted light uses orbital angular momentum (OAM) to encode information, instead of polarization, a more common option. The researchers were able to show that by using OAM and angular position they could encode a seven dimensional, or letter alphabet with the photons. This alphabet is important for quantum key distribution (QKD), which is the start of quantum cryptography. To use QKD the users will encode the key with this alphabet onto the photons. Only if both the sender and receiver are measuring along the same dimension will they get the same key, and by comparing what was original sent and received, both parties can determine the key without publicly transmitting what it is. An eavesdropper would disrupt the transmission in a detectable way, thereby allowing the users to avoid interception.

Thus far the researchers have demonstrated their system working at 4 kHz with 93% accuracy, so the researchers still have some work to do before reaching the long term goal of a GHz rate. Besides the quantum cryptography applications, this new system also allows for each photon to carry 2.05 bits of information, but with more sophisticated equipment, the photons could hold 4.17 bits, and allow for an even more secure 25 letter alphabet.

Source: University of Rochester



Again, Quantum Mechanics Defies Intuition

Category: Science & Technology
Posted: March 20, 2015 02:25PM
Author: Guest_Jim_*

It really should not come as a surprise that researchers have found another way that quantum mechanics defies conventional logic. One of the possible uses for quantum computing is finding items in large data sets, because there are quantum algorithms that can search far faster than any conventional system. The structure of the data set will impact the speed of the search, but researchers at the University of California, San Diego have found that the less connected it is, the faster the quantum algorithm will go.

One would expect that if you were searching for something, the easier it is to move around, the faster you would find what you are looking for. When the researchers actually modelled this scenario though, as well as a less connected system, they found the superposition-exploiting algorithm was faster with the low-connectivity system.

Source: University of California, San Diego



Finding How the Brain Learns Technical Concepts

Category: Science & Technology
Posted: March 20, 2015 07:15AM
Author: Guest_Jim_*

Have you ever wondered about the cognitive processes behind learning? Researchers at Carnegie Mellon University have, and now they have some answers as they have recently watched how the brain behaves while learning about different mechanical systems. Such information could help improve science instruction and possibly more.

To perform the study, the researchers scanned the brains of 16 adults while they learned, for the first time, how four mechanical systems work. This instruction came by way of a series of images, diagrams, and text, and covered how a bathroom scale, fire extinguisher, car brakes, and a trumpet works. To the researchers' surprise, there were different stages to the brain activity during the process. As the explanations began visually, those regions of the brain are what activated in the first stage, but then other parts lit up when the subjects were mentally visualizing how the system works, and the causal chain. At the end, regions of the brain involved with imagining how a person would interact with the system were active.

The researchers also found that when the people learned that both fire extinguishers and car brakes utilize force being exerted on a fluid, the brain would represent the two very different systems similarly. This suggests how the brain can gain a fundamental understanding of things, at a deep level, which could be useful to teach to.

Source: Carnegie Mellon University



Highest Peak-Power Laser Diode Arrays have been Deployed

Category: Science & Technology
Posted: March 19, 2015 02:36PM
Author: Guest_Jim_*

Lasers are critical for a great variety of scientific studies, and so there is a constant effort to develop better, more powerful lasers to delve deeper into science. To that end, researchers at Lawrence Livermore National Laboratory have installed and commissioned laser diode arrays with a peak power of 3.2 megawatts, which is the highest in the world.

These arrays represent a major leap in the technology as they use a new pump technology. For the past 50 years, flashlamps have been used to dump white light into laser glass, to pump atoms to the necessary excited energy state. While this has worked very well for decades, they can only fire a pulse about once a second, and the High-Repetition-Rate Advanced Petawatt Laser System (HAPLS) has a goal of one petawatt at a rate of 10 Hz. The new diode arrays are a main component to HAPLS. To achieve the higher rate, the researchers turned to Lasertel Inc., which used micro-optics to create the pump modules. LLNL also developed a new pulsed-power system that and precisely shaped electrical pulses at 40,000 amps.

One day HAPLS, with these new arrays, could be used to advance our studies of particle acceleration, biophysics, chemistry, quantum mechanics, and laser fusion. The new technologies also allow for a bright future, with potential long-term scalability.

Source: Lawrence Livermore National Laboratory



Nonlinear Metamaterials for Improved Computers in the Future

Category: Science & Technology
Posted: March 19, 2015 06:58AM
Author: Guest_Jim_*

I do not doubt that the joke has been made that the future of computing is a bright one, as many researchers are working to replace electronics with photonics, or electronic-photonic hybrid systems. Now researchers at Tel Aviv University have discovered a way to exploit new, nonlinear metamaterials to make active optical devices.

Metamaterials are simply defined as man-made materials with properties impossible to find in Nature, such as negative indices of refraction. Recently, nonlinear metamaterials have been created that are able to magnify nonlinear optical phenomena. Nonlinear materials are able to directly affect light waves that enter them, like significantly shifting their frequency. What the Tel Aviv researchers have discovered is a design for nonlinear metamaterial devices that allow for control over the interaction between the metamaterial and light.

The active control these devices would enable could be used to create new, high-speed computer chips and be used for on-chip communications. For now though, the researchers want to see if they can make the devices more efficient by using multiple layers, and studying what different metamaterial building blocks will do.

Source: American Friends of Tel Aviv University



Graphene Can be a Gateway for Protons

Category: Science & Technology
Posted: March 18, 2015 01:59PM
Author: Guest_Jim_*

Another potential application has been added to the already long list for graphene, a form of carbon. Researchers at ORNL and Northwestern University have discovered that protons are able to slip through a graphene membrane, even while other small particles are stopped. This could prove invaluable for technologies that require managing protons, such as fuel cells.

Graphene is an atom-thick sheet of carbon with a hexagonal pattern to it, resembling chicken wire, at least in its ideal form. Defects will of course exist in a slice, such as gaps where a carbon atom is missing. The researchers have found that these gaps can act as gateways for protons, or hydrogen nuclei, to slip through. To verify this, the researchers put a piece of single-layer graphene on a substrate of silica glass, with water molecules separating them. They then varied the acidity of the solution on both sides of the graphene, and watched chemical changes around the graphene using a laser technique called second harmonic generation. To confirm it was happening at these defects, the researchers used ORNL's aberration-corrected scanning transmission electron microscope, which is able to actually image the individual carbon atoms.

A critical part of hydrogen fuel cells is a membrane that only lets protons through, as it means that electrons have to go through a circuit to finally meet up with a proton again. With graphene acting as a membrane, it may be possible to reduce the size and weight of fuel cells, improve their efficiency, and perhaps more.

Source: Oak Ridge National Laboratory



Audio Encoded Onto Plasmonic Nanostructure for First Time

Category: Science & Technology
Posted: March 18, 2015 06:29AM
Author: Guest_Jim_*

Optical sound was developed in the 1920s in part as a way to bring talking to movies. Now, almost a century later, optical sound has returned as a means to encode audio onto special nanoantennas. Researchers at the University of Illinois have done this to demonstrate the information storage potential of their new pillar-supported bowtie nanoantennas (pBNAs).

The pBNAs are made of gold and just 250 nm across, though the pillars they are on are 500 nm tall. Those pillars are actually very important to their information storage capabilities as they cause the gold to heat up when hit by low-powered laser light. This subtle melting changes the gold's optical response, which can be viewed under white-light illumination, and is what actually stores the information; in this case Twinkle, Twinkle, Little Star. While the information was stored as analog data, thanks to the spectral degree-of-freedom afforded by the plasmonics involved, it would be possible to use this to store digital data instead.

Compared to magnetic film for analog data storage, the pBNAs can store 5600 times more, which gives it great potential for storage applications. By altering the size of the nanoantennas, it may even be possible to store more information with them.

Source: University of Illinois



How Geckos Keep Clean Discovered

Category: Science & Technology
Posted: March 17, 2015 02:10PM
Author: Guest_Jim_*

Geckos are already known for exploiting one physical phenomenon, van der Waals force, for climbing up seemingly any surface, but it turns out this is not the only trick the animals use. Researchers at James Cook University and elsewhere have discovered that gecko bodies are superhydrophobic, which keeps them cleaning, even in dusty deserts.

Under an electron microscope, the researchers were able to find that geckos have tiny hair-like spines all over their skin. These spines create a very bumpy surface on the micro and nano scale, which causes water droplets on it to just roll off, instead of sticking. If multiple droplets combine, they will actually launch themselves off the skin, as the merger releases energy. Any dust and dirt particles on the skin will be dragged away by the water droplets at the same time, so even those geckos that live in dusty deserts will keep clean, as dew does the trick.

Hydrophobic surfaces are already known for their self-cleaning properties and some plant and insect species have been discovered to take advantage of the phenomenon. This is the first time that it has ever been observed in a vertebrate though.

Source: James Cook University



Robust Self-Cleaning Paint Created

Category: Science & Technology
Posted: March 17, 2015 06:54AM
Author: Guest_Jim_*

Many people love the idea of self-cleaning objects, as it removes or at least reduces the work we have to do and in some cases and prolong the life of the object. To achieve this, the surface of the object is made superhydrophobic, so water just beads on it, but the superhydrophobic materials we make tend to be very fragile. Researchers at University College London, Imperial College London, and Dalian University have succeeded in making a superhydrophobic paint that can coat various materials and survives damage.

Superhydrophobic materials are self-cleaning because they repel water so strongly, that any water that hits them just beads and rolls off, taking dirt away with it. If the material is damaged or exposed to oil however, this effect can be lost. To preserve it, the researchers created a paint of coated titanium dioxide nanoparticles and combined it with various adhesives, depending on the material to be coated. The adhesive prevented the coating from being removed by normal wear and tear.

The researchers have tested their paint on various materials, including steel, glass, cotton, and even paper, and all of them became self-cleaning. Because they used readily available materials, their method can be scaled up for industrial purposes.

 

 

Source: University College London



Superconductivity Observed at Fastest Speed Yet

Category: Science & Technology
Posted: March 16, 2015 02:44PM
Author: Guest_Jim_*

High speed cameras were first used over one hundred years ago to determine if the hooves of a galloping horse are ever off the ground at the same time. Ever since then, high speed photography has been used to observe a variety of events, and now researchers at the University of British Columbia have developed a new technique to capture the behavior of electrons in superconductors.

Superconductors are materials capable of transmitting electrical currents without resistance, and have been, understandably, of great interest since their discovery. Unfortunately the low temperatures required have limited their use, but by better understanding how the phenomenon occurs, researchers hope to devise room temperatures superconductors. To that end, the UBC researchers combined technologies and techniques to capture the behavior of electrons over just 10 femtoseconds (0.00000000000001 seconds).

The results support the hypothesis that the interactions between one electron and the spin and magnetic pull of the others around it actually delay and mediate electrons interacting with each other.

Source: University of British Columbia



Silk Used to Make Better Batteries

Category: Science & Technology
Posted: March 16, 2015 05:28AM
Author: Guest_Jim_*

The world would be a very different place if we had not developed batteries, especially lithium-ion batteries as they have enabled us to create the powerful yet portable devices we rely on every day. As we continue to demand better performance from our devices, we will have to find some way to improve the batteries that power them. As reported by the American Chemical Society in its journal ACS Nano, researchers may have found a solution from silk.

Many modern energy storage technologies rely on graphite electrodes for storing energy, but it has its limits. To push past those limits, the researchers looked to other carbon sources and found a material derived from silk to replace graphite. The carbon-based nanosheets the researchers created have five times the lithium storage capacity as graphite, which means batteries using them could store substantially more power. Of course storing more power means little of the batteries lack stability, but when tested the material survived 10,000 charge/discharge cycles with only a 9% loss.

The process the researchers used to create their prototype batteries and supercapacitors are single-step and can be easily scaled up.

Source: American Chemical Society



Finding How Heat Propagates in Graphene

Category: Science & Technology
Posted: March 13, 2015 03:06PM
Author: Guest_Jim_*

Among the many impressive characteristics of graphene is its great thermal conductance, which some would like to see used to assist in the cooling of electronics. Before that can happen though, we must learn why the 2D material conducts heat so well. Researchers at EPFL have apparently achieved just that with a new model that may apply to other 2D materials.

Graphene is an allotrope of carbon, like graphite and diamond, but is effectively two dimensional, as it is just an atom thick. This causes it to have a number of curious properties that do not exist in 3D materials, and is part of the reason it is so different from most other materials. For example, in a 3D material, the phonons that carry heat through it will constantly hit each other and either merge or split, which limits thermal conductivity. What the EPFL researchers found is that phonons travel as waves in graphene, using a phenomenon called second sound. In 3D materials this phenomenon only occurs at temperatures near absolute zero, but graphene exhibits it at room temperature.

While this research will definitely impact current and future work with graphene, it is not limited to the one material. Potentially many other 2D materials exhibit the same phonon behavior, which may prove invaluable for designing future electronics.

Source: Ecole Polytechnique Fédérale de Lausanne



New Thrusters Made for Small Satellites

Category: Science & Technology
Posted: March 13, 2015 06:55AM
Author: Guest_Jim_*

Some people may envision the satellites orbiting above our heads as large, million dollar machines, but more and more small, cheap satellites are being put up. Even though they can be the size of a softball, a lot can be packed into them, but one crucial has been all but missing. These satellites lack the thrusters that are necessary to maintain their orbits, but researchers at MIT have formed a spin-off company, Accion, with a new solution.

This new solution is an electrospray thruster, and its current MAX-1 system consists of eight chips, one square centimeter by two millimeters thick, and a plastic fuel tank. In this case the fuel is a nontoxid, nonvolatile liquid-salt propellant. The chips are placed above the tank, each chip has a porous substrate with about 500 pointed tips on it, and above the tips is an extractor grid. The propellant is drawn to the tips by capillary forces, and when a high voltage is applied to the tips and grid, the propellant is ionized and shoots out from the holes, producing thrust in the opposite direction. The thrust is only enough to move a piece of paper on Earth, but in orbit, it is enough for a small satellite to maneuver with.

Thanks to its relatively simple design, the MAX-1 has a higher thrust-to-mass ratio than other low-power, ion engines, making it a more attractive option. Low-cost chemical-propulsion systems could be made, but as the fuel is not allowed to be carried up on the same rockets as the satellites usually are, they are not really an option.

Source: MIT



New Means of Growing Semiconductor Crystals Discovered

Category: Science & Technology
Posted: March 12, 2015 02:01PM
Author: Guest_Jim_*

I suspect that most of you already know that the electronics we use daily are made of stacked semiconductor crystals. What you may not realize is the importance of these layers being aligned, and how difficult that can be to achieve. Misalignment between the layers introduces defects that degrade efficiency, but researchers at Kansas State University have found a new way to grow the layers that is better at minimizing these defects.

The researchers first happened upon this new method years ago, when they found a particularly smooth substrate sample. In collaboration with researchers at the State University of New York and the University of Bristol, it was confirmed that the layers present on the substrate had fewer defects than normal. Now the researchers have applied this method of growing crystals of other materials and are working to confirm that it is applicable to more than just some specific materials.

Source: Kansas State University



Means to Making Glass More Durable Discovered

Category: Science & Technology
Posted: March 12, 2015 06:21AM
Author: Guest_Jim_*

Glass is a very unusual material that can be found all around us, as windows and in our various displays. What makes it and other glass-like materials so odd is that it does not exactly cool to become a solid, but instead a frozen liquid state. This can allow it to lose durability over time as it relaxes, but researchers at UCLA and the Université Pierre et Marie Curie have found a way to prevent that.

When glass cools, its molecules take on a chaotic structure, as opposed to a regular, crystal structure, but it is this structure that gives it, its strength. As it is exposed to various temperatures and pressures though, that structure can relax and the strength is lost, making it unusable. What the UCLA researchers have found is that by making the glass under certain conditions, it can be made to retain its properties throughout its life. This retention of properties is called thermal reversibility and has to do with optimizing the angles the molecular bonds have with each other.

While more durable screens, windows, and optical cables are definitely valuable, this research will likely impact other materials, including cement. The structure within cement is similar enough to glass that it also suffers from relaxation over time, so by similarly optimizing how it is produced, better concrete can be made.

Source: University of California, Los Angeles



Entanglement Proven Useful for Optical Sensors

Category: Science & Technology
Posted: March 11, 2015 03:04PM
Author: Guest_Jim_*

Many quantum mechanical phenomena will collapse down to classical physics when entering the environment. This begs the question then of if these phenomena can ever be of use when we know they will collapse. According to researchers at MIT, the answer is yes, at least for entangled photons.

Quantum entanglement is when the state of one particle constrains the state of another, so by knowing the state of one you know the state of the other. For some time it has been wondered if entangled photons could be useful for optical sensors, since the entanglement is going to break down as the probing light travels through the environment. According to the MIT researchers, entanglement will still improve the sensor because while the quality of the probe beam does degrade, compared to a reference beam used to filter out noise, the two beams being entangled gives them a better starting point. The light beam will degrade the same amount regardless of if it is entangled or not, but because the correlation between the entangled beams is stronger to begin with, the signal-to-noise ratio is better than compared to completely classical beams.

So far the researchers have shown a 20% increase in the signal-to-noise ratio this way, but it could go much higher, doubling or quadrupling, with better optical equipment. As detection error is exponentially related to the signal-to-noise ratio, this could result in a million-fold increase in sensitivity.

Source: MIT



New IT Architecture Developed for Cars

Category: Science & Technology
Posted: March 11, 2015 06:57AM
Author: Guest_Jim_*

Cars have had computers in them for a long time, but many modern cars now feature computers meant to serve the driver as much as the car. While these new capabilities are certainly appreciated by many drivers, the underlying systems were not designed to support them. Researchers at TU München, as part of the Visio.M project, have decided to change that by developing a new architecture for the computer systems.

This new architecture is similar to that used in smartphones, with functions split between two subsystems. This separation provides protection from attacks, by placing the vital functions on one subsystem and everything else on the other. Connecting every component is the Automotive Service Bus, which the researchers created and acts as a message channel. The components send messages along this channel, but only have read access to vehicle data, except in clearly defined situations. These messages fall into three groups: Events that provide information; commands for interactions between components; and preferences with driver-specific data. Again like smartphones, this design allows the components to be updated, changed, or deleted but without having to visit any special station to do so.

To foster development, the researchers are placing the Automotive Service Bus under an open source license.

Source: TU München



Hybrid Film Developed for Touchscreens

Category: Science & Technology
Posted: March 10, 2015 02:24PM
Author: Guest_Jim_*

Chances are that every day many of us interact with at least one touchscreen, and if that would happen to be the one in our phones, we are probably also somewhat protective of it. At least I know I do not want to risk breaking the screen, which is why there is a lot invested into finding ways to prevent this damage. One approach is to use less brittle materials in the touchscreen, and The Optical Society's Optical Materials Express journal has published a paper recently describing such a new material.

Traditionally indium tin oxide (ITO) has been used in our touchscreens, because it is a transparent conductor, but it is also very fragile and somewhat expensive. While some have been looking at organic thin films to replace ITO, the new paper describes using a hybrid film instead. The hybrid film contains both organic and inorganic materials to achieve the necessary optical and electrical properties. In fact, compared to glass the hybrid layers are 96% to 100% transparent, while still survive 10,000 bending cycles without resistance increasing too much.

Just as important as its transparency and flexibility is that the hybrid thin film can be made very cheaply in solution, at low temperatures, and without a high-vacuum. It can even be made with enough layers to act as an anti-reflective coating, which may allow for new applications.

Source: The Optical Society



HP Announces More Efficient Cartridges for Laser Printers

Category: Science & Technology
Posted: March 10, 2015 12:34PM
Author: Brentt Moore

HP has officially announced all new cartridges for its laser printers, which according to the company, are capable of offering 58 percent more color pages and 28 percent more black-and-white prints compared to current cartridge technology. The increased efficiency is based on refinements in the chemical formula that makes up the laser printer cartridges currently offered by HP. The refinements allow the new cartridges to not only offer a higher page count from the same sized product, but also the same page count rating with smaller cartridges.

Unfortunately for users, the more efficient laser printer cartridges will only be available for new LaserJets. The new cartridges will first make their way into entry-level LaserJets recently announced by HP, and will be offered in advanced multifunction printers later this year.

Source: PCWorld



Smartphone Use and Lazy Thinking Linked

Category: Science & Technology
Posted: March 10, 2015 06:15AM
Author: Guest_Jim_*

Some of you may have seen this coming, but according to researchers at the University of Waterloo, there is a link between smartphone use and weaker cognitive abilities. More specifically, the use of search engines as social media and entertainment applications showed no such link.

According to the researchers' study, which involved 660 people, it relates to the kind of thinker we are. Intuitive thinkers, who rely on gut feelings and instincts, are more likely to turn to search engines on our smartphones than putting in the cognitive effort to arrive at an answer. Analytical thinkers however, who are more likely to second-guess themselves and apply logic to a problem, were less likely to turn to the search engines in our pockets and purses. This indicates a link between heavy smartphone use and lower intelligence, but whether smartphone use actually impacts intelligence is still to be determined.

This research aligns with previous work indicating that humans try to avoid effort when solving problems, so using smartphones as an extended mind makes sense. How this may affect our psychology is still to be determined though.

Source: University of Waterloo



Combining Light and Sound for Better Signal Processing

Category: Science & Technology
Posted: March 9, 2015 02:01PM
Author: Guest_Jim_*


For a long time, researchers have been working to develop better ways to process signals, such as turning to optics from electronics for smaller sizes and greater bandwidths. By incorporating acoustics as well, it may be possible to push the boundaries even farther, and now Yale University researchers have created a device that can manipulate both photons and phonons.

We may not think much about sound for use in computers, since the waves travel so slow, but they can store information for longer and in a smaller space than optical signals can. With circuits that can control both, the Yale researchers are able to get the best of both worlds. Not only that, but the size of their circuitry is small enough that it can be integrated into microchips, allowing for more efficient storage, filtering, and manipulation of signals.

Source: Yale University



Watching Dendrites Grow

Category: Science & Technology
Posted: March 9, 2015 05:31AM
Author: Guest_Jim_*

Personally I have never had a battery burst into flames, but I have had some swell on me, and lose performance. The reason this happens is to do with tiny structures called dendrites that form within lithium-ion batteries, and have proven somewhat difficult to stop. Researchers at ORNL, however, have now, for the first time, imaged the formation of these structures in real time, which could help defeat them one day.

As the name suggests, lithium-ion batteries use lithium ions to store energy and normally they stay in solution or in one of the electrodes. Sometimes though, they will collect together to form solid structures called dendrites. As the dendrites grow, they may puncture the protective layer between the electrodes, causing a short circuit. Obviously this is a bad thing, which is why a lot of work has been done to protect against them, but the ORNL researchers are the first to directly image dendrites forming. To do this, they created an electrochemical cell to mimic the inside of a lithium-ion battery, applied a voltage, and had it under a scanning transmission electron microscope. The result was a series of images showing how the dendrites develop, at high resolution.

Typically studies concerning how a battery fails, wait until after the battery does, but this research and method allows researchers to watch the process unfold. This new approach could aid in the development of additives and new separators to prevent dendrites and preserve batteries better.

 

 

Source: Oak Ridge National Laboratory



New Device for Correcting Quantum Errors

Category: Science & Technology
Posted: March 6, 2015 02:51PM
Author: Guest_Jim_*

We are approaching a revolution in computing, when the first quantum computer is built and allows new kinds of algorithms to be run. Much has to be done before then though, including error detection and correction schemes. Researchers at the University of California, Santa Barbara have recently developed just such a scheme that is the first capable of correcting its own errors.

At the heart of quantum computer's capabilities are the qubits it uses to store and process information. Unlike traditional bits that can represent a 0 or 1, a qubit, or quantum bit, is able to exploit superposition to represent 0 and 1 at the same time. Superposition, like other quantum phenomena, is very fragile, so qubits are prone to flip or losing their information, hence the need of systems to prevent that from happening. The California researchers' solution was to build a device of nine qubits that protect the data each other holds. By repeating the error detection and correction process, the data can be preserved for longer than a solitary qubit can.

While this is definitely an important tool, more work is needed including ways to guard against other kinds of error, such as one call 'phase flip.' The researchers also want to see what happens when the error correction cycles are made to run for greater amounts of time, and if this results in new kinds of behavior.

Source: University of California, Santa Barbara



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