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Proteus, the Shape-Shifting and Possibly Non-Cuttable Material

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How cool would it be if there was a material that couldn’t be cut or drilled into? You could make the baddest bike lock, the toughest-toed work boots, or the most secure door. Really, the list of possibilities just goes on and on.

Proteus chews through an angle grinder disc in seconds.

Researchers from the UK and Germany claim that they’ve created such a magical material. It can destroy angle grinder discs, resist drill bits, and widen the streams of water jet cutters.

The material is made of aluminium foam that’s embedded with a bunch of small ceramic spheres. It works by inducing retaliatory vibrations into the cutting tools, which turns the tools’ force back on themselves and quickly dulls their edges.

The creators have named the material Proteus after the elusive and shape-shifting prophet of Greek mythology who would only share his visions of the future with those who could get their arms around him and keep him still. It sounds like this material could give Proteus a run for his money.

The ceramic spheres themselves aren’t indestructible, but they’re not supposed to be. Abrading the spheres only makes Proteus stronger. As the cutting tool contacts them, they’re crushed into dust that fills the voids in the aluminium foam, strengthening the material’s destructive vibratory effect. The physical inspiration for Proteus comes from protective hierarchical structures in nature, like the impact-resistant rind of grapefruit and the tendency of abalone shells to resist fracture under the impact of shark teeth.

How It’s Made

Proteus recipe in pictures.

At this point, Proteus is a proof of concept. Adjustments would likely have to be made before it can be produced at any type of scale. Even so, the recipe seems pretty straightforward. First, an aluminium alloy powder is mixed with a foaming agent. Then the mixture is cold compacted in a compressor and extruded in dense rods. The rods are cut down to size and then arranged along with the ceramic spheres in a layered grid, like a metallurgical lasagna.

The grid is spot-welded into a steel box and then put into a furnace for 15-20 minutes. Inside the furnace, the foaming agent releases hydrogen gas, which introduces voids into the aluminium foam and gives it a cellular structure.

Effects of cutting into a cylinder of Proteus with an angle grinder.

According to their paper, the researchers tried to penetrate the material with an angle grinder, a water jet cutter, and a drill. Of these, the drill has the best chance of getting through because the small point of contact can find gaps more easily, so it’s less likely to hit a ceramic sphere. The researchers also made cylindrical samples without steel cladding which they used to test the compressive strength and prove Proteus’ utility as a structural material for beams and columns. It didn’t fare well initially, but became less compressible as the foam matrix collapsed.

The creation process lends some leeway for customization, because the porosity of the aluminium foam can be varied by changing the bake time. As for the drill bit problem, tightening up security is as easy as adjusting the size and/or density of the ceramic spheres.

In the video after the break, you can watch a chunk of Proteus eat up an angle grinder disc in under a minute. Some may argue about the tool wielder’s technique, but we think there’s something to be said for any material that can destroy a cutting disc that fast. They don’t claim that Proteus is completely impenetrable, but it does look impressive. We wish they would have tried more cutting tools like a gas torch, or experimented with other destructive techniques, like plastic explosives, but we suppose that research budgets only go so far.

Images via Nature



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Community Testing Suggests Bias in Twitter’s Cropping Algorithm

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With social media and online services are now huge parts of daily life to the point that our entire world is being shaped by algorithms. Arcane in their workings, they are responsible for the content we see and the adverts we’re shown. Just as importantly, they decide what is hidden from view as well.

Important: Much of this post discusses the performance of a live website algorithm. Some of the links in this post may not perform as reported if viewed at a later date. 

The initial Zoom problem that brought Twitter’s issues to light.

Recently, [Colin Madland] posted some screenshots of a Zoom meeting to Twitter, pointing out how Zoom’s background detection algorithm had improperly erased the head of a colleague with darker skin. In doing so, [Colin] noticed a strange effect — although the screenshot he submitted shows both of their faces, Twitter would always crop the image to show just his light-skinned face, no matter the image orientation. The Twitter community raced to explore the problem, and the fallout was swift.

Intentions != Results

An example pair of source images posted to Twitter, featuring two faces in alternate orientations.

Twitter users began to iterate on the problem, testing over and over again with different images. Stock photo models were used, as well as newsreaders, and images of Lenny and Carl from the Simpsons,  In the majority of cases, Twitter’s algorithm cropped images to focus on the lighter-skinned face in a photo. In perhaps the most ridiculous example, the algorithm cropped to a black comedian pretending to be white over a normal image of the same comedian.

The result – Twitter’s algorithm crops on the white face, regardless of orientation.

Many experiments were undertaken, controlling for factors such as differing backgrounds, clothing, or image sharpness. Regardless, the effect persisted, leading Twitter to speak officially on the issue. A spokesperson for the company stated “Our team did test for bias before shipping the model and did not find evidence of racial or gender bias in our testing. But it’s clear from these examples that we’ve got more analysis to do. We’ll continue to share what we learn, what actions we take, and will open source our analysis so others can review and replicate.”

There’s little evidence to suggest that such a bias was purposely coded into the cropping algorithm; certainly, Twitter doesn’t publically mention any such intent in their blog post on the technology back in 2018. Regardless of this fact, the problem does exist, with negative consequences for those impacted. While a simple image crop may not sound like much, it has the effect of reducing the visibility of affected people and excluding them from online spaces. The problem has been highlighted before, too. In this set of images of a group of AI commentators from January of 2019, the Twitter image crop focused on men’s faces, and women’s chests. The dual standard is particularly damaging in professional contexts, where women and people of color may find themselves seemingly objectified, or cut out entirely, thanks to the machinations of a mysterious algorithm.

The problem remained consistent in many community tests, involving newsreaders, cartoons, and even golden and black labradors.

Former employees, like [Ferenc Huszár], have also spoken on the issue — particularly about the testing process the product went through prior to launch. It suggests that testing was done to explore this issue, with regards to bias on race and gender. Similarly, [Zehan Wang], currently an engineering lead for Twitter, has stated that these issues were investigated as far back as 2017 without any major bias found.

It’s a difficult problem to parse, as the algorithm is, for all intents and purposes, a black box. Twitter users are obviously unable to observe the source code that governs the algorithm’s behaviour, and thus testing on the live site is the only viable way for anyone outside of the company to research the issue. Much of this has been done ad-hoc, with selection bias likely playing a role. Those looking for a problem will be sure to find one, and more likely to ignore evidence that counters this assumption.

Efforts are being made to investigate the issue more scientifically, using many studio-shot sample images to attempt to find a bias. However, even these efforts have come under criticism – namely, that using an source image set designed for machine learning and shot in perfect studio lighting against a white background is not realistically representative of real images that users post to Twitter.

Some users attempted to put the cause down to issues of contrast, saturation, or similar reasons. Whether or not this is a potential cause is inconclusive. Regardless, if your algorithm will only recognise people of color if they’re digitally retouched, you have a problem.

Twitter’s algorithm isn’t the first technology to be accused of racial bias; from soap dispensers to healthcare, these problems have been seen before. Fundamentally though, if Twitter is to solve the problem to anyone’s satisfaction, more work is needed. A much wider battery of tests, featuring a broad sampling of real-world images, needs to be undertaken, and the methodology and results shared with the public. Anything less than this, and it’s unlikely that Twitter will be able to convince the wider userbase that its software isn’t failing minorities. Given that there are gains to be made in understanding machine learning systems, we expect research will continue at a rapid pace to solve the issue.



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Anti-Piracy Group Seeks Owners Of YTS, Pirate Bay And Others

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The Alliance for Creativity and Entertainment (ACE) is attempting to uncover the owners of pirate sites like YTS, Pirate Bay, Tamilrockers, and several others.

For that purpose, ACE previously filed a DMCA subpoena that requires Cloudflare to unveil operators of several pirate sites. According to the latest report from Torrent Freak, a total of 46 high profile pirate websites have been named by the anti-piracy coalition.

ACE is an anti-piracy organization that crackdowns on the operators of pirate websites. Some of its members include Amazon, Netflix, Disney, and Paramount Pictures. The latest targets of this crackdown are pirate sites using Cloudflare. For the uninitiated, Cloudflare is a content delivery network (CDN) service provider used by millions of websites globally.

In the first half of 2020, Cloudflare received 31 such requests, concerning 83 accounts, most of which were related to adult sites.

The current subpoena targets 46 pirate websites, including some big fish like Pirate Bay, YTS, 1337x, 123Movies, and more. Once in action, it’ll force Cloudflare to reveal the IP addresses, emails, names, physical addresses, phone numbers, and payment methods of the people operating these websites.

Here is the list of domains that ACE wants to gather information on —

  • yts.mx
  • pelisplus.me
  • 1337x.to F
  • seasonvar.ru
  • cuevana3.io
  • kinogo.by
  • thepiratebay.org
  • lordfilm.cx
  • swatchseries.to
  • eztv.io
  • 123movies.la
  • megadede.com
  • sorozatbarat.online
  • cinecalidad.is
  • limetorrents.info
  • cinecalidad.to
  • kimcartoon.to F
  • tamilrockers.ws
  • cima4u.io
  • fullhdfilmizlesene.co
  • yggtorrent.si
  • time2watch.io
  • online-filmek.me
  • lordfilms-s.pw
  • extremedown.video
  • streamkiste.tv
  • dontorrent.org
  • kinozal.tv
  • fanserial.net
  • 5movies.to
  • altadefinizione.group
  • cpasmieux.org
  • primewire.li
  • primewire.ag
  • primewire.vc
  • series9.to
  • europixhd.io
  • oxtorrent.pw
  • pirateproxy.voto
  • rarbgmirror.org
  • rlsbb.ru
  • gnula.se
  • rarbgproxied.org
  • seriespapaya.nu
  • tirexo.com
  • cb01.events
  • kinox.to
  • filmstoon.pro
  • descargasdd.net

Earlier in August, it was reported that torrent giant YTS had revealed user data with a law firm. This led to the users receiving letters from the law firm, asking them to pay around $1,000 for using the pirate site or be named in a lawsuit for piracy.

Recently, ACE has set out on a crusade to banish pirate websites. While there has been no significant action from the group in the past few years, 2020 is seeing increasing activity in reporting and controlling piracy.

The post Anti-Piracy Group Seeks Owners Of YTS, Pirate Bay And Others appeared first on Fossbytes.



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Google is making a major change to one of the best Chrome features

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  • Google announced that the Chrome browser will shut down support for paid extensions, advising developers to make appropriate changes as the feature is deprecated.
  • Google explained that the web has evolved dramatically since the introduction of the Chrome Web Store, and developers have other tools at their disposal to monetize content.
  • The deprecation of the extension payments feature should also bolster the security of Chrome, preventing spammy extensions and scams from harming users.

Google’s Chrome internet browser may be a resource hog that kills laptop batteries, but it’s still the most popular browser in the world. One of the things that make it so popular is the support for extensions that can significantly improve one’s browsing experience. That’s an area where Apple’s Safari lags behind, and one reason I’ve stayed with Chrome on the MacBook for years.

But Google plans a significant change for Chrome shortly — well, another major change — that will impact Chrome extension developers directly. Google is now shutting down paid Chrome extensions, telling developers that they will have to find a new way to charge their customers.

Google put up a support page that addresses the change and the timeline for the update. The Chrome Web Store Payments deprecation will not happen instantly, so developers have time to make the appropriate changes. But all payments will be disabled by February 1st, 2021. Here’s what will happen once we reach that deadline:

Your existing items and in-app purchases can no longer charge money with Chrome Web Store payments. You can still query license information for previously paid purchases and subscriptions. (The licensing API will accurately reflect the status of active subscriptions, but these subscriptions won’t auto-renew.)

Developers who want to charge money for new extensions will not be able to do so and will have to find other ways of monetizing their Chrome apps.

Google isn’t shutting the door to monetization completely, it’s just the Chrome Web Store Payments system that’s shutting down, and Google. Developers will have to migrate to a different payment processor, and they’ll have to migrate license tracking as well. This may sound like a task for developers only, but Google does not that users might need to “help:”

There is no way to bulk export your existing user licenses, so you need to have your users help with this part of the migration.

In other words, if you’re paying for any Chrome extension, you should make sure you have your license ready when the time comes to transition to something else, especially if you’re on some subscription plan.

Google explains that the web “has come a long way” since the Chrome Web Store was launched, and that’s why things are changing. “In the years since, the ecosystem has grown, and developers now have many payment-handling options available to them,” Google says.

One other reason to remove Chrome Web Store payment support concerns user security. Google confirmed earlier this year an uptick in the number of fraudulent transactions that involved Chrome extensions, having temporarily disabled publishing paid items in late January.



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