A Graphene Mouth Screen

We are all intimate with face coverings to slow the spread of the coronavirus. Some are reusable, and some become waste after one use. [Dr. Ye Ruquan] and a research team from City University of Hong Kong, CityU, are developing an inexpensive reusable mask with outstanding antibacterial properties, and, get this, the graphene it contains will generate a tiny current when moistened by human breath. There isn’t enough power to charge your phone or anything, but that voltage drops as the masks get dirty, so it can help determine when it needs cleaning. The video after the break shows the voltage test, and it reminds us of those batteries.

All the remarkable qualities of this mask come from laser-induced graphene. The lab is producing LIG by lasering polyimide film with a commercial CO2 infrared model. In a speed test, the process can convert 100cm² in ninety seconds, so the masks can be made more cheaply than an N95 version with that melt-blown layer that is none too good for the earth. Testing the antibacterial properties against activated carbon fiber and blown masks showed approximately 80% of the bacteria is inert after 8 hours compared to the others in the single digits. If you put them in the sun for 10 minutes, blown fabric goes to over 85%, but the graphene is 99.998%, which means that one bacteria in 50K survives. The exact mechanism isn’t known, but [Dr. Ye] thinks it may have something to do with graphene’s sharp edges and hydrophobic quality. A couple of coronavirus species were also affected, and the species that causes COVID-19 will be tested this year.

An overly damp mask is nothing to sneeze at, so keep yourself in check and keep yourself fabulous.

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Nvidia Acquires ARM For $40 Billion

Nvidia announced on Sunday evening that it has reached an agreement to acquire Arm Limited from SoftBank for a cool $40 billion.

In this age of headlines that use the b-word in place of nine zeros it’s easy to lose track, so you may be wondering, didn’t SoftBank just buy Arm? That was all the way back in July of 2016 to the tune of $32 billion. SoftBank is a holding company, so that deal didn’t ruffle any feathers, but this week’s move by Nvidia might.

Arm Limited is the company behind the ARM architecture, but they don’t actually produce the chips themselves, instead licensing them to other companies who pay a fee to use the core design and build their own chip around it. Nvidia licenses the ARM core for some of their chips, and with this deal they will be in a position to set terms for how their competitors may license the ARM core. The deal still needs regulatory approval so time will tell if this becomes a kink in the acquisition plan.

There’s a good chance that you’re reading this article on a device that contains an ARM processor because of its dominance in the smartphone and tablet market. Although less common in the laptop market, and nearly unheard of in the desktop market, the tide may be changing as Apple announced early in the summer that their Mac line will be moving to ARM.

Chances are you know the Nvidia name for their role as purveyors of fine graphics cards. They got a major boost as the world ramped up Bitcoin and other cryptocurrency mining hardware which early on was mainly based on the heavy lifting of graphics processors. But the company also has their eye on the ongoing wave of hardware targeting AI applications like computer vision. Nvidia’s line of Jetson boards, marketed for “next-generation autonomous machines”, all feature ARM cores.

Assuming the deal goes through without a hitch, what will be the fallout? Your guess is as good ours. There is certainly a conflict of interest in a company who competes in the ARM market owning the Arm. But it’s impossible to say what efforts they will make to firewall those parts of the business. Some might predict a mass exodus from the ARM ecosystem in favor of an open standard like RISC-V, but that is unlikely in the near-term. Momentum is difficult to overcome — look at how long it took ARM to climb that mountain and it was primarily the advent of a new mobile ecosystem lacking an established dominant player that let ARM thrive.

Security This Week: Racoons In My TLS, Bypassing Frontends, And Obscurity

Raccoon is the next flashy security flaw with a name, cute logo, and a website (and a PDF). Raccoon is a flaw in TLS version prior to 1.3, and seems to be a clever bit of work, albeit one with limited real-world application. The central problem is that these older versions of TLS, when using Diffie Hellman (DH), drop leading all-zero bytes in the resulting pre-master key. As that key is part of the input for calculating the master session key, a shortened pre-master key results in a slightly faster calculation of the master key. If an attacker can make fine-grained timing measurements, he can determine when the pre-master key is trimmed.

Let’s review Diffie Hellman, briefly. The client and server agree on two numeric values, a base g and modulus p, and each party generates a secret key, a and b. Each party calculates a public key by raising the shared base to their own private key, mod the shared modulus: A = g^a mod p. These public keys are exchanged, and each party raises the received key to their own secret key: A^b. Exponents have a non-obvious quirk, the power rule. A value raised to a power raised to a power is the same as the value raised to the power of the exponents multiplied together. g^a^b is equal to g^(a*b). By going through this mathematical dance, the server and client have arrived at a shared value that only they know, while preserving the secrecy of their private keys. Continue reading “Security This Week: Racoons In My TLS, Bypassing Frontends, And Obscurity”

Game Boy Plays Forever

For those of us old enough to experience it first hand, the original Game Boy was pretty incredible, but did have one major downside: battery consumption. In the 90s rechargeable batteries weren’t common, which led to most of us playing our handhelds beside power outlets. Some modern takes on the classic Game Boy address these concerns with modern hardware, but this group from the Delft University of Technology and Northwestern has created a Game Boy clone that doesn’t need any batteries at all, even though it can play games indefinitely.

This build was a proof-of-concept for something called “intermittent computing” which allows a computer to remain in a state of processing limbo until it gets enough energy to perform the next computation. The Game Boy clone, fully compatible with the original Game Boy hardware, is equipped with many tiny solar panels which can harvest energy and is able to halt itself and store its state in nonvolatile memory if it detects that there isn’t enough energy available to continue. This means that Super Mario Land isn’t exactly playable, but other games that aren’t as action-packed can be enjoyed with very little impact in gameplay.

The researchers note that it’ll be a long time before their energy-aware platform becomes commonplace in devices and replaces batteries, but they do think that internet-connected devices that don’t need to be constantly running or powered up would be a good start. There are already some low-powered options available that can keep their displays active when everything else is off, so hopefully we will see even more energy-efficient options in the near future.

Thanks to [Sascho] for the tip!

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ISS Ham Radio Repeater

There is a long history of spacecraft carrying ham radio gear, as the Space Shuttle, Mir, and the ISS have all had hams aboard with gear capable of talking to the Earth. However, this month, the ISS started operating an FM repeater that isn’t too dissimilar from a terrestrial repeater. You can see [TechMinds] video on the repeater, below.

The repeater has a 2 meter uplink and a 70 centimeter downlink. While you can use a garden variety dual-band ham transceiver to use the repeater, you’ll probably need a special antenna along with special operating techniques.

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New Zealand To Test Wireless Power Transmission

Nikola Tesla wanted to beam power without wires. NASA talked about building power-generating satellites that would do the same thing. But now New Zealand’s second-largest power utility — Powerco — is working with a start-up company to beam energy to remote locations. There have been several news releases, but possibly the most technical detail is from an interview [Loz Blain] did with the founder of the startup company.

It isn’t really news that you can send radio waves somewhere and convert the signal back into power. Every antenna does that routinely. The question is how efficient is the power transmission and — when the power levels are high — how safe is it? According to [Greg Kushnir], the founder of Emrod, the technology is about 70% efficient and uses ISM frequencies.

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Paper Keyboard Is Self-Powered

Building a keyboard isn’t a big project these days. Controller chips and boards are readily available, switches are easy to find, and a 3D printer can do a lot of what used to be the hard parts. But engineers at Purdue have printed a self-powered Bluetooth keyboard on an ordinary sheet of paper. You can see videos of the keyboards at work below.

The keyboards work by coating paper with a highly fluorinated coating that repels water, oil, and dust. Special inks print triboelectric circuits so that pressing your finger on a particular part of the paper generates electricity. We were skeptical that the Bluetooth part is self-powered, although maybe it is possible if you have some very low-power electronics or you manage the power generated very carefully.

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