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Science & Technology News (1280)

Cray Adds AMD Epyc to Its Supercomputer Product Line

Category: Science & Technology
Posted: April 23, 2018 09:27AM
Author: Guest_Jim_*

Cray has been a name associated with supercomputers for many decades, and last week it announced it was adding AMD Epyc 7000 processors to its Cray CS500 product line. These cluster systems will off the company's customers greater flexibility as they will not need to rebuild and recompile x86 applications to run their high-performance computing workloads. The Cray Programming Environment has been updated to support AMD Epyc by integrating and optimizing it and its libraries for the processors.

Cray CS500 cluster systems will be offered with four dual-socket nodes in a 2U chassis or a 2U chassis with only one node, for large memory configurations. The AMD Epyc 7000 processors support up to 32 cores and eight DDR4 memory channels per socket.

Source: Cray



Omniphobic Coating Should Keep Surfaces Grime Free

Category: Science & Technology
Posted: April 13, 2018 12:38PM
Author: Guest_Jim_*

Keeping the things we touch clean is not always easy, and keeping things kids touch clean is even harder. To address this, researchers at the University of Michigan have developed a new omniphobic material that is durable and transparent. Being omniphobic means it will repel water, oils, alcohols, and apparently even peanut butter.

Omniphobic materials have been made before, but this one stands out because it is durable and clear as well, which are two properties that were a challenge to achieve. One might think that if you want a material to be both hydrophobic and oleophobic, you can just mix two with those properties, but materials science is far from that easy. Achieving the desired durability required consideration of partial miscibility, which concerns how well two substances mix, and the better they mix the more durable the result. To find the right chemicals to mix, the researchers also turned to a new approach for identifying chemicals with desirable properties. Traditionally researchers would just mix chemicals together to see what they get, but thanks to the extensive libraries of already studied materials and powerful computers, we have the ability to mathematically predict the properties of new materials and mixtures.

Ultimately the researchers found a mix of fluorinated polyurethane and F-POSS, a repellent molecule does the job while being clear and durable. While fluorinated polyurethane is already inexpensive, F-POSS is not, but manufacturers are in the process of scaling up to mass production, which will reduce the cost significantly. For now the researchers want to confirm the coating is nontoxic, so it could find use in daycare centers and similar, but eventually we could see it come to market in the next two years.

 

 

Source: University of Michigan



GeForce Academy of Gaming Launched

Category: Video Cards, Gaming, OCC News, Software, Science & Technology
Posted: March 30, 2018 10:49PM
Author: Grilka8050


The NVIDIA Academic Program has announced its expansion! It has added the Academy of Gaming. There are three majors, including Hardware Studies, eSports Management, and Gameosophy. These will help future developers and students create games that will change the industry. 

This starts next month, with 15 courses available at the release, and more are planned to launch throughout this year. These free courses are also transferable to nationally recognized colleges and universities. 

If you are interested in learning more, I highly recommend watching the official announcement on YouTube. If you are interested in viewing the course catalog, visit http://www.geforce.com/academy



Flexible LCD Created that Resembles Paper

Category: Science & Technology
Posted: March 29, 2018 12:25PM
Author: Guest_Jim_*

It might be the case that most of us get our information from electronic screens today, but there is still something to being able to hold a piece of paper in your hands. Trying to get the best of both media has not been easy, but researchers in China and Hong Kong have successfully created an LCD that has some paper-like qualities, including being only half a millimeter thick, flexible, and the potential to be inexpensive. A key aspect of this new display is the use of optically rewritable LCDs, unlike those used in our monitors, televisions, and phones.

An LCD is structured like a sandwich, with a layer of the liquid crystal between two plates, and in a conventional LCD the plates have electrical connections. These connections increase the thickness of the LCD, and can limit what materials and thickness used for the plates. Optically rewritable LCDs operate very differently, as special molecules on the plates react to polarized light to realign themselves, and switch the pixels. This enables such LCDs to have a much simpler structure, making them less expensive and more durable than their conventional counterparts. Additionally, the alignment of the molecules does not change without the polarized light, which means power is only needed when switching the display.

The researchers needed to do more than just work with optically rewritable LCDs, but also develop new spacers to go between the liquid crystal and the plates. Spacers are very important in any LCD, as they maintain the thickness of the liquid crystal layer, with a constant thickness necessary for a good contrast ratio, but as this LCD design needs to be flexible, the spacers need to maintain a thickness when bent. It was discovered a mesh-like spacer does the job, keeping the liquid crystal from flowing even when the LCD was bent or hit. The researchers also made it possible for the display to show three colors at a time with a special type of liquid crystal behind the LCD. The pixels will need to become smaller though, in order to produce full color, and the researchers also feel the resolution will need to increase before a commercial product could be made.

Source: EurekAlert!



Invisible Display Proof-of-Concept Created

Category: Science & Technology
Posted: March 26, 2018 11:51AM
Author: Guest_Jim_*

There are a number of works of fiction that include displays on walls and windows that do not appear to be there when not in use. An important step toward making such displays has been made by researchers at the University of California, Berkeley with the creation of light emitting devices that are invisible when off. The key to this was overcoming a limitation of LEDs on monolayer semiconductors, making it possibly to keep the device very thin but up to several millimeters wide.

To create light an LED has two contact points with one providing negative charges and the other positive charges, with the light being emitted from where the charges meet. When working with a monolayer semiconductor, in this case just three atoms thick, there is little room available for these contacts, but the researchers were able to work around this. The solution was to place the semiconductor on an insulating layer and then having electrodes on the monolayer semiconductor and beneath the insulator. By then applying an alternating current to the insulator, at the time the current switches polarity both positive and negative charges are present within the semiconductor, resulting in light.

The layers of material here are all so thin that they are flexible and transparent when not emitting light, which means the display is invisible when off and could be applied to curved surfaces. As it is though, this is just a proof-of-concept as the device's efficiency was only around 1% while that of commercial LEDs is around 25% to 30%. It might be a while longer before we see invisible display become a reality, but this is a significant step in that direction.

Source: University of California, Berkeley



NVIDIA Titan V Giving Errors in Some Scientific Workloads

Category: Science & Technology
Posted: March 26, 2018 09:29AM
Author: Guest_Jim_*

Currently one of the most powerful, and also most expensive graphics cards you could get is NVIDIA's Titan V. At $3000 this card uses a Volta GPU with 12 GB of HBM2 memory, and thanks to its Tensor cores can reach an unquestionably impressive 110 Tflops. While it is possible to use it to play games on, the Titan V actually targets those working with AI and deep learning, where high performance computing is very important. Unfortunately it appears some of these cards are not up to the task, according to an article from The Register.

Among the applications the Titan V is being used for is simulating how proteins and enzymes interact, and these simulations should return identical results when provided the same input. An engineer discovered and then told the The Register that of the four Titan Vs he tested on, two of them gave numerical errors ten percent of the time. Considering how necessary reproducibility is for scientific studies, this is far from a good development.

The exact cause is not known, though an "industry veteran" told The Register he thinks it might be memory related, with NVIDIA possibly pushing it too far. The Titan V does not have error-correcting code memory, which is a feature of the much more expensive Tesla line of accelerators. For now a recommendation being shared by some is to avoid using the Titan V until a patch can be developed and delivered.

Source: The Register



Means of Controlling Molecular Alignment on Graphene Discovered

Category: Science & Technology
Posted: March 23, 2018 10:35AM
Author: Guest_Jim_*

Since its discovery, there has been tremendous interest in graphene, an atom-thick sheet of carbon with impressive electrical and mechanical properties. It could potentially serve as a basis for future electronics, but is not the easiest material to work with currently. For one thing, trying to build up molecular structures on it is difficult because of graphene's symmetry, but researchers at Nagoya University have found a solution.

If you were to look at graphene, it resembles chicken wire with its hexagonal pattern, which creates a problem as it has three-fold symmetry, making those three axes thermodynamically equivalent. If you want to grow structures on a graphene sheet, the molecules you deposit equally like being on any of these axes. While working with sodium dodecyl sulfate (SDS) the researchers discovered they could control the direction it would form ribbon-like structures in. It is already known to form these structures, but they grow where they wish. After injecting SDS onto the graphene surface, the researchers used an atomic force microscope (AFM) to scan it and confirm random adsorption (which is different from absorption) of the SDS. Fifteen minutes later the surface was scanned again, but now the SDS had changed their orientation.

After some more work, the researchers discovered the AFM scanning the surface caused the SDS molecules to remove themselves from their original position to and then rotate to match the scanning orientation. The more extreme the angle between the AFM scan the direction, the more easily the SDS molecules rotated and moved, while those with a smaller different changed less and acted as seed molecules for the others. This ability to control the orientation of these ribbons could lead to several advances in many fields that work with two-dimensional materials, and could even help lead to graphene-based electronics.

Source: Nagoya University



Air-Breathing Electric Thruster Created for Low-Orbit Satellites

Category: Science & Technology
Posted: March 6, 2018 10:52AM
Author: Guest_Jim_*

What goes up must come down, is an old but accurate saying that poses a problem for satellite missions, especially those in low orbit. While the atmosphere 200 Km up is thin, it is still present enough to produce drag on a satellite, decaying its orbit. To compensate for this a thruster can be used, but once its propellant supply runs out, the satellite will fall from orbit, just like what happened to the GOCE gravity-mapping mission. For GOCE the propellant was xenon, but thanks to new work by the European Space Agency, future low-orbit missions, both for around Earth and potentially other worlds, air-breathing thrusters may be used instead.

This new thruster had to overcome the challenge of air molecules bouncing away at the intake, instead of being collected and compressed, but this was achieved. Once collected the molecules can be given an electric charge and propelled from the back producing thrust. The only parts that need any power are the coils and electrodes, with the remainder working on a passive basis, making the thruster simpler and efficient.

To test the innovative intake, normally one would feed it and measure the density at the collector, but instead the researchers decided to have the electric thruster attached and measure the thrust produced. Initially a stream of xenon was used, to confirm it was working, but then a feed of nitrogen-oxygen air replaced it, and the switch could be visibly observed by watching the engine plume change color. The system was then ignited successfully and repeatedly, confirming the feasibility of this design.

By using an air-breathing design, this removes the need for a special propellant on a satellite mission, making it possible for the satellite to continue its mission for a longer period of time. Also, as it can work with other kinds of gases, it could be used to enable satellite missions in low-orbit around a planet like Mars, with the carbon dioxide in its atmosphere serving as the propellant.

Source: ESA



Atmospheres and Densities Analyzed for Four TRAPPIST-1 Planets

Category: Science & Technology
Posted: February 6, 2018 01:43PM
Author: Guest_Jim_*

Last year NASA announced the star TRAPPIST-1 had seven Earth-sized planets orbiting it with multiple inside its habitable zone. Naturally these planets have been more closely looked at since, to determine if any of the planets might be able to support life. Using several space and ground-based telescopes, including the Hubble and Spitzer Space Telescopes, we now know that three of these exoplanets do not have high concentrations of hydrogen in their atmosphere. This is important as it suggests their atmospheres could be similar to Earth's, as opposed to the atmospheres on gaseous planets like Neptune.

The four planets investigated were TRAPPIST-1d, e, f, and g, which are the four that exist within the star's habitable zone, though one is at the inner-edge of this zone. The habitable zone of a star is the area in which a planet could have liquid water on its surface, which is necessary for life as we know it. Being a dwarf star, TRAPPIST-1 is much smaller and colder than the Sun, so much so all of its planets, not just those in the habitable zone, are closer to it than Mercury.

To analyze the planets' atmospheres, the telescopes looked at them as they transited TRAPPIST-1, so the star's light would pass through the atmospheric gases. This would leave a fingerprint of the gases on the observed spectra of the light and from that we could determine some of the atmospheres' characteristics. In addition to studying their atmosphere, the densities of the planets were also better measured, indicating the planets are mostly made of rock and some may have up to five percent of their mass in water. That would be 250 times more water than the oceans on Earth.

More observations and analyses are going to be necessary to further understand these planets 40 light years away, and likely those discoveries will come from the James Webb Space Telescope that should be launching next year. This next telescope has been designed and developed to far exceed the capabilities of the Hubble Space Telescope, but it has only been because of Hubble and other telescopes that we know what technologies and approaches get the most information.

The embedded media are from the ESA Hubble website with one being a comparison of star habitable zones.

 

Source: Hubble [NASA], [ESA] and Spitzer




Volumetric Display Made The Builds 3D Images In Air

Category: Science & Technology
Posted: February 1, 2018 09:21AM
Author: Guest_Jim_*

Science fiction has promised us many things for the future and thankfully we have scientists around the world working to fulfill those promises. Researchers at Brigham Young University are among them as they worked on their 'Princess Leia project' and they have now succeeded in creating a system to project 3D images in open air. These are not holograms though, as those involve scattering light on a 2D surface, but volumetric images as they exist in three dimensions, allowing you to view it from all sides. Other teams of researchers have also been working on producing volumetric imagery, but this is the first to combine the optical trapping and colorful lasers.

The way this display works is to take a particle of cellulose and trap it with a laser. This trapping allows the laser to precisely move it around while another set of lasers illuminate and color it. Thanks to how quickly the particle is being moved around, persistence of vision makes it appear lines are being painted in mid-air, forming a volumetric image. The researchers liken it to a 3D printer for light, with the cellulose particle effectively printing light as it is move around.

Thus far the researchers have displayed volumetric images of a butterfly, a prism, the university's logo, rings wrapped around an arm, and a recreation of Princess Leia by an individual in a lab coat crouching much as Leia does at the beginning of the famous message.

 

 

Source: Brigham Young University



Broadband Achieved Over Wet String

Category: Science & Technology
Posted: December 13, 2017 12:49PM
Author: Guest_Jim_*

Physics is an amazing thing, especially when you turn it to something kind of silly. An employee at a British IP did just this by demonstrating a broadband, ADSL signal can be carried by wet string. To be more specific, it was two meters of string soaked in salt water because fresh water would not do the trick. After connecting the string, its speed was measured at 3.5 Mbps for download, proving it works.

Why does this work? Because the physics involved with the signal does not solely rely on an electric current, which the string would resist. Instead the cable acts as a waveguide for electromagnetic waves of such high frequency, the material does not matter much.

It is safe to say string is not going to become a part of broadband connections, but this still demonstrates an interesting and amusing quirk to the technologies so many of us use every day.

Source: RevK's Rants Blog



All of the Top 500 Supercomputers Now Run Linux

Category: Science & Technology
Posted: November 16, 2017 10:18AM
Author: Guest_Jim_*

While it might not be a common operating system among consumers, Linux now dominates among supercomputers. All of those on the TOP500 list of the world's fastest supercomputers use the open-source operating system, and it is that open-source nature that has helped it achieve this milestone. Many supercomputers today are built for specific tasks, and to get the most out of them, customized operating systems are desired. Instead of developing a new OS from scratch, the open-source code of Linux allows the optimizations to be developed and put in place at much lower cost.

Source: ZDNet



Iridium Can Be Used to Destroy Cancer Cells

Category: Science & Technology
Posted: November 3, 2017 01:08PM
Author: Guest_Jim_*

Iridium is a rather rare metal, and while it is associated with the asteroid that led to the mass extinction of the dinosaurs and much more life, it may come to be a powerful tool for preserving life. Researchers at the University of Warwick have discovered a means to use iridium to destroy cancer cells, and this method does not damage normal healthy cells.

To destroy the cancer cells, the researchers made a compound of iridium and an organic material, and then light just needs to shine on it. The compound can be targeted specifically at cancerous cells, and it will transfer the energy of the light to the oxygen within the cell, producing singlet oxygen. Singlet oxygen is a high-energy form of oxygen that is highly reactive and poisonous to the cancer cell. Healthy cells are not affected by this process though, and the researchers even tested the method in healthy cells to prove as much. The light used in the process is just visible light and for their testing the researchers used red laser light, as it can reach through the skin.

While this research is on its own impressive, it also shows the value in exploring even more precious metals for their use in cancer chemotherapies. Platinum, another precious metal, is already used in over half of such treatments, and others could prove equally potent.

Source: University of Warwick



Improved Memory Management Developed for On-chip DRAM

Category: Science & Technology
Posted: October 23, 2017 11:06AM
Author: Guest_Jim_*

As processors have become faster and faster, the time it takes to go off-chip to access data has become more and an issue. This is where on-chip high-bandwidth caches come in, and even why some have been adding DRAM to a chip's packaging. The problem is DRAM is significantly different from the SRAM typically used for on-chip caches, which is why MIT researchers have developed a new cache management system.

The critical difference between SRAM and DRAM concerns how the two memory technologies store data and the impact this has on locating specific data. All data is tagged with a piece of metadata identifying where it is also located in the system's main memory and these tags are run through a hash function. The purpose of this hashing is to produce very different values for actually similar pieces of information, as this will prevent bottlenecking at specific locations. The outputs of the hash function is stored in a hash table, and sometimes multiple data items are referenced by one entry, if they all share the same hash output, but checking these few items is still more efficient than going through the entire tag list. This is where the difference between SRAM and DRAM comes out though, as SRAM uses six transistors for each bit of data while DRAM uses only one. This does give DRAM an advantage in space efficiency, but SRAM has some processing capability, allowing it to search the hash table for the desired information, while the processor needs to do this for DRAM-stored data, which takes time and bandwidth.

The solution from MIT, which has been dubbed Banshee, adds three bits to each entry in the hash table, with one identifying if it can be found in the DRAM cache, and the other two giving a location relative to the other data items sharing the same hash index. As the entry in the table is already around 100 bits, this is not much overhead especially as it can increase the data rate of on-chip DRAM by 33 to 50%. Banshee also adds a tag buffer to address issues of one processor core not knowing when another has data put in the DRAM cache. The buffer is only 5 KB, so it does not take up much, and when it is full all of the cores have their virtual-memory tables updated, allowing the buffer to clear and start fresh.

Source: MIT



Wireless Data and Power Combined

Category: Science & Technology
Posted: September 18, 2017 11:02AM
Author: Guest_Jim_*

In recent years there has been a trend for technologies to go wireless for both form and convenience. Wireless charging is among the advancements being added to technologies, but it often comes at increased cost and weight because it requires special components be added to the device. While there is a reason these parts need to be added, instead of using those already present, researchers at North Carolina State University decided to see if it was possible to work around this reason, and succeeded.

Wireless systems, for data or power, require the use of antennas and radios and typically these parts will be tuned design for their intended purpose for greatest efficiency. For wireless power the parts are tuned to a narrow bandwidth, which minimizes power loss but makes them unsuited for data transfer. What dawned on the researchers is that while the wireless power system does require narrow band antennas, the whole system bandwidth does not need to be so small. By combining narrow-bandwidth components with a wide-bandwidth system, the researchers were able to achieve both power and data transfer.

When the researchers tested this new design, they were able to transfer 3 W of power while transmitting 3.39 MB/s with only a 2.3% loss in efficiency due to the data transmission. If only 2 W of power was transferred though, the efficiency only dropped by 1.3%. These tests were not done with the device resting directly on the charging pad with, but a little more than six inches away, demonstrating that this system can work over a distance.

Source: North Carolina State University



AI Recreates Game Engine by Watching Gameplay Videos

Category: Science & Technology
Posted: September 12, 2017 10:33AM
Author: Guest_Jim_*

Games and artificial intelligence are not exactly strangers as there have been various kinds of AIs in games for years. In the future though, we might see AI playing a role in creating the games and not just giving us opponents. This is thanks to researchers at Georgia Institute of Technology where they have made an AI that can recreate a game's engine after watching video of it.

As the AI watches video of a game, it studies the frames to construct a model of how the game works and how players will interact with it. The researchers started it on Super Mario Bros. with a speedrunner video, which would be a more difficult test for it as the player is focused just on the goal. One video was not enough to develop a model that will clone the original engine, but by providing the AI additional videos, it was able to create something accurate enough another AI could not distinguish between it and the original game.

Since working with Super Mario Bros., the researchers have moved on to experimenting with Mega Man and Sonic the Hedgehog. Ultimately we could see this turned into a tool to accelerate game development and to experiment with different kinds of gameplay.

Source: Georgia Institute of Technology



Unknown Semiconductor Behavior Discovered with Potential Efficiency Impact

Category: Science & Technology
Posted: September 6, 2017 11:32AM
Author: Guest_Jim_*

When thinking about the semiconductors within our computers and other devices, as we surely do at times, chances are we just think about silicon, but there are more materials than that one involved. On its own, silicon actually will not conduct electricity, which is why other molecules called dopants are added to the material, but adding too many doping molecules will eventually block the electrical currents. The cause of this increased resistance is believed to be from the electrons bouncing off of the dopants, but now researchers at the University of Illinois at Chicago have discovered another mechanism that increases resistance.

To make this discovery the researchers started with chips of cadmium sulfide for their semiconductor base and then used copper ions as the dopant. Instead of connecting the chips up run a current through them, the researchers instead shot a powerful blue laser at them, with the energy of the laser being enough to generate an electrical current. Very high energy X-ray images were taken at the same time just millionths of a microsecond apart to reveal what was going on. To the researchers' surprise, the copper ions were intermittently forming bonds with the semiconductor base, and these bonds were then impairing conduction.

This behavior has not been seen before and it would be impairing the speed and efficiency of the semiconductor computers it affects. Fortunately, now that we are aware of this dynamic it will be possible to create designs that minimize it.

Source: University of Illinois at Chicago



Researchers Found Action Games Can Impact Brain Matter

Category: Science & Technology
Posted: August 14, 2017 10:27AM
Author: Guest_Jim_*

For many years people have been studying what impacts video games can have on humans and producing various results. New researchers at McGill University have found that action games can actually lead to a loss of grey matter in the hippocampus, though what long-term consequences this may entail require further study. However, playing 3D-platform games, like Super Mario 64, can actually increase the amount of grey matter.

For this study the researchers had 64 participants ranging in age from 18 to 30 and had them play 90 hours of different kinds of games. These games included first person shooters like Call of Duty, Killzone, Medal of Honor, and Borderlands 2, along with the previously mentioned Super Mario 64, and the participants had not played these games previously. The researchers found that for some of those playing the FPS games, the hippocampus lost grey matter after 90 hours, while no one lost any while playing the 3D platformer, or even saw an increase. There is more to it than this though as the researchers found the loss of grey matter also depended on the kind of learner people are. Response learners, who will follow their brain's autopilot and reward system for navigation, experienced the loss while spatial learners who use the hippocampus to navigate saw an increase in grey matter. It is not just a matter of the kind of game you are playing but also how you learn. The increase seen from Super Mario 64 occurred for both types of gamers.

Exactly what about this genre causes this atrophy is still unknown and will require further study, as will determining the long-term consequences of this loss. People with lower amounts of grey matter in the hippocampus though are known to be at an increased risk of neuropsychiatric illnesses, such as depression, schizophrenia, PTSD, and Alzheimer's disease.

Source: McGill University



Nearly Perfect Single-Crystal Graphene Grown on a Large Scale

Category: Science & Technology
Posted: August 10, 2017 03:22PM
Author: Guest_Jim_*

Since its discovery, many people have been working very hard to bring graphene to various products, thanks to its strength, flexibility, and very high conductivity. One of the primary issues with the material has been the difficultly of synthesizing it, especially on large scales. Researchers at the Institute for Basic Science in Korea have discovered a possible solution though, growing large pieces of single-crystal graphene quickly and possibly without an upper-size limit.

Graphene is an atom-thick sheet of carbon with a hexagonal molecular structure to it that can transport electrons at a very high speed, while still being very strong, very flexible, and transparent. These properties give it the potential to very successfully replace silicon in electronics, but achieving this would require large, high quality pieces of the carbon allotrope. Polycrystalline graphene, which consists of many crystals that interface with each other at various angles, can be produced at large sizes, but those varied interfaces are defects that impair the material's performance, so single-crystal graphene is needed. Previously producing just a few square centimeters would require a couple hours, but this new method was able to produce a 250 cm2 (5x50 cm 2) piece of nearly perfect graphene in just 20 minutes. The researchers accomplished this by starting with a copper-foil substrate that was heated to around 1030 ºC, allowing its atoms to align, forming a single crystal of copper. Then carbon atoms were deposited onto it via chemical vapor deposition, and these atoms formed islands that eventually coalesced to make a nearly perfect, single-crystal of graphene.

Obviously this is terrific news for the future of graphene, especially as it may be possible to scale it up just by using larger pieces of copper, while still being fast and cheap. It could also lead to new ways of producing other 2D materials with special and desirable properties.

Source: Institute for Basic Science



System Developed for Optimizing Use of Caches

Category: Science & Technology
Posted: July 10, 2017 02:25PM
Author: Guest_Jim_*

A fundamental part of every processor is its caches, where the cores can keep what information they need for performing the operations assigned to them. As these caches are on on-chip, accessing them is very fast, but that does not mean there are not better ways to allocate the cache space among the cores. Researchers at MIT have developed a system called Jenga that finds the optimal distribution of not only the local cache but also DRAM for a CPU.

Two advantages to having caches built into a chip are that accessing the data in the caches is very fast and it takes little energy to do so, compared to off-chip memory. This makes optimizing the use of a chip's cache rather valuable, but modern chips need to be designed as a compromise between the capacity and latency needs of various programs. What Jenga does is measure the latency between each processor core and each cache it can access and uses that information to build a cache hierarchy. The hierarchy considers the differences between different levels of cache, like the on-chip L1, L2, and L3 caches but Jenga actually also makes measurements for using DRAM. Once the optimal cache level is determined, algorithms from an older system called Jigsaw are used to optimally allocate the caches for the entire chip. Jenga builds on Jigsaw by considering cache level in its algorithms, but the Jigsaw algorithms for optimizing along the latency-capacity curve are still valid once level is determined.

The researchers tested Jenga by simulating a system with 36 cores and found it could increase processing speed by 20-30% while reducing energy consumption by 30-85%. A fairly significant improvement for something that just improves how the hardware is used, and as more and more cores are added to CPUs, this could become an even more valuable system.

Source: MIT



3D RRAM Chip Combines Data Storage and Computing

Category: Science & Technology
Posted: July 6, 2017 11:10AM
Author: Guest_Jim_*

The rate of innovation is always increasing as new creations lead to more new projects, but this progress is not uniform. In some instances the ability to produce something can come to outpace the ability to use it, and this is happening with data currently. Right now we have the ability to generate more data than many systems can efficiently handle, but there are many researchers working to change that, including some at MIT and Stanford University where a very advanced chip has been created that combines data storage and processing.

This new chip combines two technologies that can still be considered futuristic for computers; carbon nanotubes and a 3D architecture. Modern computer chips have a 2D design, though some have a 2.5D design with layers stacked and connected to each other. The benefit to a full 3D design is that the multiple parts of the chip are able to communicate with each other much more quickly and efficiently than what is currently possible. Carbon nanotubes can also take this to a new level as their small size and electrical properties allow the chips to be made denser. In this case the chip is a form of resistive random-access memory (RRAM), which is a kind of nonvolatile memory and has some one million RRAM cells and two million carbon nanotube field-effect transistors. This combination of memory and computing removes the bandwidth bottleneck between data and processing that is an issue with today's largest datasets.

To prove the capabilities of this design, the researchers also added over one million nanotube-based sensors for detecting and classifying gases. The measurements from the sensors were processed all in parallel and written directly to memory, thanks to this integrated design of emerging nanotechnologies. What makes this accomplishment even more impressive is that the chip is compatible with CMOS, so such an RRAM chip could be combined with current silicon chips and there is a fair chance there will be many more applications for this design in the future.

Source: MIT



Study Suggests Network Traffic Can Help Stop Malware Attack

Category: Science & Technology
Posted: May 22, 2017 11:20AM
Author: Guest_Jim_*

Before large malware attacks, systems need to be infected by the malware, where it can linger undetected for weeks or months. Until a sample of the malware is discovered, traditional anti-virus software cannot remove it, but researchers at Georgia Institute of Technology, with collaboration from EURECOM and the IMDEA Software Institute, have found a way to help catch malware before it is activated. The key is monitoring network traffic.

For many pieces of malware, it needs to communicate with command and control computers, and this communication naturally involves network traffic. The researchers looked at over five billion network events from five years of ISP data and the DNS requests made by 27 million malware samples, and then compared them to the re-registration of expired domains. Such domains are often used as the launch sites for malware attacks and certain networks are more prone to abuse than others. Interestingly though, there were often months of lag time between a domain name being re-registered and attacks starting. To help with this work, the researchers created a filtering system to distinguish between benign and malicious traffic, which also involved the largest malware classification to date, differentiating malware from potentially unwanted programs.

In the end the researchers found there were signals of malware infection weeks to months before the malware was found. For this defense strategy to work though, network administrators will need to learn what normal behavior is for their networks so that bad activity can be identified, but it still indicates how the next generation of defense mechanisms can be designed.

Source: Georgia Institute of Technology



Lithium Batteries Improved by Graphene-Nanotube Hybrid

Category: Science & Technology
Posted: May 19, 2017 12:01PM
Author: Guest_Jim_*

It is beyond any doubt that lithium-ion batteries have significantly impacted the world with their high energy density and ability to be recharged. Unfortunately they are also fairly near their current limits, without the development of new technology. Many researchers and institutions are working such technologies and those at Rice University have recently created a battery with three times the capacity of what we see today.

What makes this new battery special is that its anode is not made of graphite, but a hybrid of graphene and carbon nanotubes. This hybrid is actually a metal and can hold more lithium ions than modern batteries, but most importantly it overcomes an issue common with other lithium-metal batteries. Dendrites are lithium structures that can grow inside of a battery, crossing the electrolyte possible connecting the two electrodes, causing a short circuit. Such a short circuit could cause the battery to fail, catch on fire, or explode. The hybrid materials has a high surface area and a low density, which is a valuable combination as it means the lithium particles are free to move in and out as the battery charges and discharges. This also allows the lithium to evenly distribute itself, which suppresses dendrite growth.

The prototype batteries the researchers have built have their capacity limited by the cathode, but this anode material is still able to hold near the theoretical limit of 10 times more energy than traditional lithium-ion batteries. When tested, the full batteries also were able to retain 80% of their capacity after some 500 charge-discharge cycles and were free of dendrites when examined with an electron microscope.

Source: Rice University



Transparent Semiconductor Thin Film with Record Conductivity Discovered

Category: Science & Technology
Posted: May 8, 2017 11:38AM
Author: Guest_Jim_*

You might not realize it, but a lot of the devices you rely on everyday probably include some amount of the material indium. This is because indium tin oxide (ITO) is a transparent conductor, making it ideal for use in flat-panel displays and solar cells, but indium is also rather rare, which is why so many have been looking for a viable replacement. Researchers at the University of Minnesota have recently discovered a transparent semiconductor that has the highest-ever conductivity of a thin film oxide semiconductor.

This new material is barium stannate (BaSnO3), a combination of barium, tin, and oxygen. It is a semiconductor with a wide band gap, which is important as this allows it to be transparent. The bandgap is the amount of energy it takes for an electron to enter the conduction band of a material, where it can move about freely. Typically semiconductors with wide bandgaps have low conductivity, but this is an exception, meaning the conducting film could be used in various electronic devices in the future. With barium and tin both being much cheaper than indium, there will certainly be a great interest in it.

The next step is to reduce the defects that form in the material, further improving its conductivity.

Source: University of Minnesota



Water Interlayer Found to Improve New Energy Storage Device

Category: Science & Technology
Posted: May 1, 2017 09:56AM
Author: Guest_Jim_*

When it comes to storing electrical energy the two dominant choices are batteries and capacitors. Batteries can store a great deal of energy but capacitors can charge and discharge significantly faster, so there has been a lot of effort to create a device that combines their properties. Researchers at North Carolina State University have created a proof-of-concept material that may help lead to exactly that.

For their work, the researchers were using crystalline tungsten oxide and a layered, crystalline tungsten oxide hydrate, which is almost identical except for atomically thin layers of water between the tungsten oxide layers. When the researchers charged the two materials for ten minutes, they found the regular tungsten oxide stored more energy than the hydrate, but after charging for just 12 seconds, the hydrate stored more. The hydrate also was more efficient at storing this energy, losing less to heat.

Currently this is just a proof-of-concept for the idea of adding layers of solvents, like water, to materials to tune the ability for a material to transport ions between layers. Potentially this could be used to create thinner batteries, increased acceleration for electric vehicles, and faster storage for power grids using renewable energy sources. The researchers are now moving forward with National Science Foundation-funded work to tune the interlayer and hopefully improve their understanding of these materials.

Source: North Carolina State University



3D Stacked Memory Developed to Aid Graphics Processing

Category: Science & Technology
Posted: April 27, 2017 12:05PM
Author: Guest_Jim_*

Researchers at the Pacific Northwest National Laboratory and University of Houston have developed a means to increase 3D rendering speeds by up to 65%. It involves leveraging the logic layer that exists within 3D stacked memory to do some processing within the memory, instead of putting it on the GPU.

The PNNL researchers normally work with supercomputers, but when one of them asked if 3D stacked memory could be used to help render 3D graphics, the attention shifted towards video games. Science will still benefit from this work though, as 3D rendering is used with visualizations, models, and virtual reality. During their testing on Doom 3 and Half-life 2, the researchers found the best step to have the memory process is one of the last steps, anisotropic filtering as it often creates a lot of traffic on the graphics card. By removing this traffic and performing the filtering as the first step, they found the greatest performance boost.

Source: Pacific Northwest National Laboratory



Coating Developed for Improving Lithium Ion Batteries

Category: Science & Technology
Posted: April 18, 2017 12:44PM
Author: Guest_Jim_*

The invention of lithium-ion batteries has made many other technologies possible, thanks to the high energy density they give us. However, we are always looking for more and the current battery design has limits, as do possible alternatives. Researchers at the University of California, Riverside have found a possible way to break one of those alternative's limits with an inexpensive coating.

Inside of every battery is a cathode and anode, the electrodes for the positive and negative charged sides respectively. Graphite and other carbon materials are currently used in lithium-ion batteries for the anode, because it works well and is rather resilient. A lithium metal anode would be far superior though, providing up two ten times the energy density, but lacks that resiliency as dendrites form from the anode, cutting its lifespan short. What the researchers discovered is that by adding methyl viologen to the electrolyte, the ion-containing fluid between the electrodes, a coating would form over the lithium metal as the organic molecules touch the metal, preventing dendrite growth.

The researchers have already found that the methyl viologen can triple the cycling lifetime of the battery, which is truly significant and could be increased with further investigation. It is also worth noting that methyl viologen is very low in cost and is already compatible with manufacturing lithium ion batteries.

Source: University of California, Riverside



Material Made That Draws Moisture From Dry Air

Category: Science & Technology
Posted: April 14, 2017 11:07AM
Author: Guest_Jim_*

Water is a compound necessary for human life but is not always accessible. To help with that, researchers at MIT have created a device using a metal-organic framework originally invented at Berkeley Lab that can collect moisture from even dry air and use sunlight to then release it.

A metal-organic framework (MOF) is exactly what it sounds like as it combines metal with organic molecules to create porous, rigid structures. These structures can be used to hold gases and liquids. In this case zirconium metal is used with adipic acid and the result is a MOF that loves water and can pull it out of air as dry as a desert, just 20-30% humidity. The solar-powered harvester that was built uses just one kilogram of the MOF, but is able to generate 2.8 liters of water from that arid air after just 12 hours.

Obviously this invention is very significant as it can bring water to so many people who need it, but we may see something even better coming in the future. This particular MOF is only able to absorb 20% of its weight in water, but there are others that may be able to reach 40%, and it should also be possible to tune the material for specific humidities.

 

 

Source: Berkeley Lab



Thin and Smooth Layer of Silver Could Advance Displays and Computers

Category: Science & Technology
Posted: March 24, 2017 12:51PM
Author: Guest_Jim_*

For a long time the material indium tin oxide (ITO) has been a requirement in several technologies because it is a transparent conductor. One issue with ITO is that indium is quite rare, making the material ever more expensive, and another is that it is rather fragile. A potential alternative for a transparent conductor is a silver ultrathin film, which has issues of its own but researchers at the University of Michigan have recently solved some of these.

When trying to create a thin film of silver, it typically cannot be smaller than 15 nm because silver likes to cluster into islands and not form an even coating. What the Michigan researchers discovered is that adding just 6% aluminum the silver can be coaxed to form a film just 7 nm thick. After applying an anti-reflective coating they were able to make one layer up to 92.4% transparent. The aluminum is even more useful than that though, as the ultrathin film did not tarnish in open air after months, unlike pure silver films that tarnish almost immediately, disrupting its conductive properties and transparency.

While there are some obvious uses in displays, this silver ultrathin film has far more potential than that. In this form, silver is able to carry plasmon polaritons, which are oscillations created when light strikes a metal and they carry the information of the light wave. Plasmons can be much smaller than the wavelength of the light though, allowing the silver film to act as a kind of superlens. This gives the film potential uses inside of computer chips as a means to transmit information optically, allowing for faster data transfer than electronic transmission currently allows. On top of that, by alternating layers of the silver film with an insulator, like glass, a metamaterial hyperlens could be made, which could then image objects smaller than the wavelength of light and enable laser patterning, such as that used to etch computer chips, to reach smaller feature sizes.

Source: University of Michigan



Battery Designed for Powering and Cooling Computer Chips

Category: Science & Technology
Posted: March 15, 2017 12:09PM
Author: Guest_Jim_*

There are a number of battery technologies out there that employ different methods to store and deliver electricity. Many store energy within their solid electrodes, but flow batteries actually use liquid electrolytes for storage. Today you can find large scale flow batteries used in stationary applications, but thanks to researchers at ETH Zurich and IBM Research Zurich we may see them coming to computing devices thanks to a clever use of the liquid electrolytes.

As the name indicates, the two liquid electrolytes in a flow battery move through it, and with the proper membrane is between them, an electrical current is produced like in any battery. What occurred to the researchers is that the electrolytes could also be used to transport heat away from a system, like a liquid cooling system for a computer. Instead of designing something comparable in size to an AIO cooler, the researchers went even smaller, making a battery just 1.5 mm thick so that it can be integrated into a chip stack. In a chip stack individual chips are stacked on top of each other to save space and energy, but by putting a thin battery micro-cell in between it is possible to power and cool the chips.

This micro-battery design offers a record-setting 1.4 W/cm2 (1 W/cm2 after subtracting the power to pump the electrolytes) and is able to dissipate more heat than what the battery generates as electrical energy. However further optimize is going to be needed because, record setting or not, it is not enough power for the computer chip to operate. Still, this is a promising proof-of-concept that may have potential in a variety of applications and could improve large-scale flow batteries as well.

Source: ETH Zurich



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