Video Engineers at MIT have created paper-thin speakers using a plastic film and a piezoelectric layer embossed with tiny domes.

These sheet speakers could potentially be applied to any surface for sound output or input: think surround sound or noise cancellation in aircraft. The technology also has potential for ultrasound imaging and echolocation, among other possibilities.

The work is described in a paper published recently in the journal IEEE Transactions on Industrial Electronics, "An Ultra-Thin Flexible Loudspeaker Based on a Piezoelectric Micro-Dome Array."

"It feels remarkable to take what looks like a slender sheet of paper, attach two clips to it, plug it into the headphone port of your computer, and start hearing sounds emanating from it," Vladimir Bulović, leader of the Organic and Nanostructured Electronics Laboratory (ONE Lab), director of MIT.nano, and senior author of the paper, told the MIT News Office.

The other two co-authors of the paper are Jinchi Han, a ONE Lab postdoc, and Jeffrey Lang, professor of electrical engineering at MIT.

The boffins have produced a short YouTube video that demonstrates the technology:

Traditional speakers translate electrical signals into a magnetic field that moves a speaker membrane to create audible vibrations. The MIT academics got rid of the coiled wire that generates the membrane-moving magnetic field by using piezoelectric material – which converts electrical energy to mechanical energy (and vice versa) – to move a microarray of domes that generate sound.

Their design relies on a sheet of plastic known as PET (polyethylene terephthalate) that's perforated and layered with a thin film of piezoelectric material, called PVDF (polyvinylidene fluoride).

When these sheets are heat bonded to create a vacuum, the result is a flat array of tiny domes that move when voltage is applied. The design creates enough separation of materials to allow the domes to vibrate without interference when the plastic film has been mounted to a surface.

At a distance of 30cm (12 inches), it's claimed, these thin-film speakers can generate high-quality sound equivalent to the volume of a typical conversation (66 decibels) through the application of 25 volts of electricity at 1 kilohertz. At 10 kilohertz, sound output reached the level of city traffic (86 decibels).

The sheet-speakers supposedly require only 100 milliwatts of power per square meter of speaker area, significantly less than home speakers that use more than 1 watt of power for comparable sound pressure at the same distance.

Jinchi Han told The Register in an email that the speakers have been tested between 100 Hz to 100 kHz.

"They are able to produce sound at low frequencies, but sensitivities (acoustic pressure generated under unit voltage) are usually higher at high frequencies than those at low frequencies," said Han.

According to the MIT News Office, the technology is simple to fabricate and can be scaled up to cover the interior of a room or vehicle – the research was funded in part by Ford Motor Company. This would allow covered surfaces to emit sound for listening or for noise cancellation.

Ioannis (John) Kymissis, professor of electrical engineering and Chair of the department of electrical engineering at Columbia University, told the MIT News Office that the technology could also be used to record sound – the domes, acting as tiny microphones, would capture vibrations.

MIT professor Jeffrey Lang confirmed as much in an email to The Register.

"The same device can work as a microphone," said Lang. "It can be mounted on the surface of any object and used for sound recording. The device itself is passive and generates voltage signal under incident acoustic waves. But we apply a small transimpedance amplifier in order to obtain a large signal-to-noise ratio."

"We actually have an upcoming paper that reports the microphonic performance of the same device. The amplifier is the only part that consumes power. If a standalone design is needed, usually the signal storage/processing and wireless transmission consume much more power than the amplifier itself."

"But we can either use a battery or integrate energy harvesting components to make it standalone without wiring to external power. For instance, our group is also developing thin-film solar cells and it's possible to integrate that with the acoustic thin film to provide the energy."

Han said the technology has potential for ultrasound applications because it can generate the high resonance frequency necessary for ultrasound imaging. Echolocation is another possible application, according to Bulović, who also suggested the micro-speaker array combined with a reflective surface could be used as a display technology by creating patterns of light. ®

David Harville, eBay's former director of global resiliency, pleaded guilty this week to five felony counts of participating in a plan to harass and intimidate journalists who were critical of the online auction business.

Harville is the last of seven former eBay employees/contractors charged by the US Justice Department to have admitted participating in a 2019 cyberstalking campaign to silence Ina and David Steiner, who publish the web newsletter and website EcommerceBytes.

Former eBay employees/contractors Philip Cooke, Brian Gilbert, Stephanie Popp, Veronica Zea, and Stephanie Stockwell previously pleaded guilty. Cooke last July was sentenced to 18 months behind bars. Gilbert, Popp, Zea and Stockwell are currently awaiting sentencing.

Just as costs for some components have started to come down, TSMC and Samsung, the two largest contract chip manufacturers in the world, are reportedly planning to increase prices of production, which may affect Nvidia, AMD, Apple, and others that rely on the foundries.

Reports emerged earlier this week stating that Taiwan-based TSMC is planning price hikes in the single-digit percentages for legacy and advanced chip manufacturing technologies next year. Citing industry sources, Nikkei reported that the price hike will be around five to eight percent.

On Friday Bloomberg reported that South Korea's Samsung is planning to raise prices for chip designers by 15-20 percent this year, citing industry sources. Legacy nodes will be hit hardest, and the new pricing will come into effect in the second half of the year.

Finnish open-source-as-a-service provider Aiven received $210 million in funding this week, adding $1 billion to its nominal valuation in just nine months.

The Series D cash injection – led by Eurazeo, and joined by funds and accounts managed by BlackRock as well as existing investors IVP, Atomico, Earlybird, World Innovation Lab, and Salesforce Ventures – follows $60 million Series C funding which valued the firm at $2 billion.

The latest investment round values the company at $3 billion. It's remarkable considering it only supports open-source software and was worth $800 million when it got its first $100 million tranche of Series C funding in March last year.

Black Hat Asia Software made unsafe by dependencies should be fixed without users needing to interact with the source of the problem, according to US National Cyber Director Chris Inglis, who serves in the Executive Office of the President.

Speaking to The Register at the Black Hat Asia conference in Singapore on Friday, Inglis said that when a faulty component in a car needs to be replaced, the manufacturer who chose that component takes responsibility for securing safe parts and arranging their installation. He contrasted that arrangement with the fix for the Log4j bug, which required users to seek assistance from both vendors that used the open-source logging code and source software from the Log4j project itself.

Inglis wants vendors to take responsibility for their choices so that addressing security issues is easier and users' systems – and the US – can achieve better resilience with less effort.

Memory and storage maker Micron Technology has revealed a new business model intended to address the volatility in the memory market that has resulted in sharp swings in pricing over the past several years.

Revealed at Micron's Investor Day 2022 event, the new forward pricing agreements enable a Micron customer to sign a multi-year deal that guarantees them a supply of memory at a predictable price that follows the cost reduction that the chipmaker sees during the lifecycle of a particular product.

Micron's chief business officer Sumit Sadana told Investor Day attendees that the chipmaker has already signed up an unnamed volume customer to one of the new agreements, which the company is currently trying out to see whether it delivers on the expected benefits.

Almost nine in 10 organizations that have suffered a ransomware attack would choose to pay the ransom if hit again, according to a new report, compared with two-thirds of those that have not experienced an attack.

The findings come from a report titled "How business executives perceive ransomware threat" by security company Kaspersky, which states that ransomware has become an ever-present threat, with 64 percent of companies surveyed already having suffered an attack, but more worryingly, that executives seem to believe that paying the ransom is a reliable way of addressing the issue.

The report, available here, is based on research involving 900 respondents across North America, South America, Africa, Russia, Europe, and Asia-Pacific. The respondents were in senior non-IT management roles at companies between 50 and 1,000 employees.

Black Hat Asia Cyber war has become an emerged aspect of broader armed conflicts, commencing before the first shot is fired, cybersecurity expert Kenneth Geers told the audience at the Black Hat Asia conference on Friday.

"Peacetime in cyberspace is a chaotic environment," said Geers, who has served as a visiting professor at Kiev National Taras Shevchenko University, represented the US government at NATO, and held senior roles at the National Security Agency. "A lot of hacking has to be done in peacetime."

Geers said the Russia-Ukraine war demonstrates how electronic and kinetic conflicts interact. Ahead of the Ukraine invasion, Russia severed network cables, commandeered satellites, whitewashed Wikipedia, and targeted military ops via mobile phone geolocations.

Canonical has begun slinging daily builds of Ubuntu at Windows Subsystem for Linux. We took a look at the not-for-production code.

Ubuntu has long been friends with the Windows Subsystem for Linux. If you pop wsl --install onto a virgin Windows 11 PC, the odds are it will be Canonical's Linux distribution that is installed by default.

There are plenty of other options available – OpenSUSE and Debian spring effortlessly to mind, and we recently noted the arrival of AlmaLinux for RHEL refuseniks, but all require specifying manually.

The Iran-linked Cobalt Mirage crew is running attacks against America for both financial gain and for cyber-espionage purposes, according to Secureworks' threat intelligence team.

The cybercriminal gang has been around since June 2020, and its most recent activities have been put into two categories. One, using ransomware to extort money, as illustrated by a strike in January against a US philanthropic organization, according to Secureworks' Counter Threat Unit (CTU); and two, gathering intelligence, with a local government network in the United States targeted in March, CTU researchers detailed today.

"The January and March incidents typify the different styles of attacks conducted by Cobalt Mirage," they wrote. "While the threat actors appear to have had a reasonable level of success gaining initial access to a wide range of targets, their ability to capitalize on that access for financial gain or intelligence collection appears limited. At a minimum, Cobalt Mirage's ability to use publicly available encryption tools for ransomware operations and mass scan-and-exploit activity to compromise organizations creates an ongoing threat."

Something for the Weekend "We all know what we're doing today? Good. Do your best!"

With that cheery note, our new project director sweeps out of the 10:00 stand-up meeting and away to… someplace or another, I don't know, wherever it is that project directors go. Project managers can be found everywhere, usually nearby a waste basket overflowing with disposable coffee cups, but project directors? Who can say?

These project directors are a mystery. It's not a job title I'd come across before. They just swan in from time to time, managerial but polite and rather vague, then drift out again with a farewell motto such as "Do your best!" or "You've all done very well!" like Young Mr Grace.

Elon Musk has hit the brakes on his proposed takeover of Twitter in light of the platform's insistence that spam accounts accounted for less than five percent of its daily active users.

The figure was raised in an SEC filing on Monday, the company's latest earning release [PDF], where it said "there are a number of false or spam accounts in existence on our platform."

The company continued in the filing: "We have performed an internal review of a sample of accounts and estimate that the average of false or spam accounts during the first quarter of 2022 represented fewer than 5 percent of our mDAU [monetizable daily active users] during the quarter."

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