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Submission + - PHEVs look great on paper, but real world data says otherwise (theguardian.com)

Submitted by shilly
shilly writes: PHEV manufacturers and advocates claim it’s easy to drive mainly using the cars’ batteries, keeping gas in reserve for long trips. That may be true in theory, but in practice, data from 800,000 PHEVs in Europe shows that between 2021 and 2023, these vehicles were driven using their batteries for just 27% of the time, instead of the 84% figure used in official estimates. It turns out that merely providing the option for driving on batteries in a car isn’t enough to persuade people to plug in, and that EV proponents, who have long argued that PHEVs are not a viable solution, have a point after all.

Submission + - How we sharpened the James Webb telescope's vision from a million kilometers awa (theconversation.com)

Submitted by schwit1
schwit1 writes: Hubble started its life seeing out of focus – its mirror had been ground precisely, but incorrectly. By looking at known stars and comparing the ideal and measured images (exactly like what optometrists do), it was possible to figure out a “prescription” for this optical error and design a lens to compensate.

The correction required seven astronauts to fly up on the Space Shuttle Endeavour in 1993 to install the new optics. Hubble orbits Earth just a few hundred kilometers above the surface, and can be reached by astronauts.

By contrast, Webb is roughly 1.5 million kilometers away – we can’t visit and service it, and need to be able to fix issues without changing any hardware.

This is where AMI comes in. This is the only Australian hardware on board, designed by astronomer Peter Tuthill.

It was put on Webb to diagnose and measure any blur in its images. Even nanometers of distortion in Webb’s 18 hexagonal primary mirrors and many internal surfaces will blur the images enough to hinder the study of planets or black holes, where sensitivity and resolution are key.

AMI filters the light with a carefully structured pattern of holes in a simple metal plate, to make it much easier to tell if there are any optical misalignments.

We wanted to use this mode to observe the birth places of planets, as well as material being sucked into black holes. But before any of this, AMI showed Webb wasn’t working entirely as hoped.

Submission + - Supershear earthquakes even more dangerous than we thought (latimes.com)

Submitted by Bruce66423
Bruce66423 writes: 'A specific type of earthquake that can cause particularly intense shaking is more common than previously believed, some scientists say — carrying potentially profound risk for communities across California, including those in the path of the notorious San Andreas fault.'

Comment Re:Isn't this admitting.... (Score 1) 126

by jalvarez13 (#65619890) Attached to: With a New Soyuz Rocket, Russia Seeks to Break Its Ukrainian Dependency

Did you decide to mention Lyapunov because Tsiolkovski was not ethnic Russian? Oh well. Anyway, what Lyapunov did was in a generic math field, not specific to space. He got noticed and published abroad. Hardly "unknown".

Actually, as a control systems engineer, Lyapunov was the first one I thought of. You may not know this, but his works were not available in english at that time. Kalman had to read the french translation, as you can see in this 1960 paper titled Control system analysis and design via the “second method” of Lyapunov

Comment Re:Isn't this admitting.... (Score 3, Informative) 126

I believe you are missing two major developments that were led by the russians: First, the contributions of Konstantin Tsiolkovsky, whose works on rocket design and fuel mix ("Exploration of Outer Space by Means of Rocket Device", parts 1 and 2) laid the foundations of what we use today. Second, Aleksandr Lyapunov who develped and advanced theory of stability in his doctoral thesis in 1892.

According to my college professor, in the 1950's US engineers didn't bother to check russian publications on any subject, because they, just like you, thought that they were ignorant peasants that had nothing to contribute. Therefore they were completely ignorant about Lyapunov's developments. The thing is that Lyapunov's stability was a key advantage that allowed the soviets to beat the US in launching the first satellite into orbit. Only then, Kalman and others began to read their papers.

By the way, the first International Federation of Automatic Control (IFAC) World Congress, was held in 1960 in Moscow.

PS: I have no preference for any country whatsoever. On the contrary, I believe that excellence in science and engineering can and do arise in many places around the world. In this context, there is no point in dismissing the russians or any other country/place.

PS2: The US response to the Sputnik crisis led to the creation of ARPA, which without any doubt has fueled the US hegemony for decades. Quite an achievement.

Comment Re:About done (Score 2) 109

by jalvarez13 (#65597280) Attached to: 5% of Americans are Cancer Survivors - and They're Living Longer

I'm sorry for your situation. I certainly cannot imagine what you are going through. At the risk of sounding impertinent --you have most certainly searched areound for the best possible treatment-- I'll share with you an article that sounded like science fiction to me, but that is a real thing: Medicine Spares Cancer Patients From Grisly Surgeries and Harsh Therapies

This is my summary:

"Immunotherapy is a treatment that until now has been used as part of a suite of tools to attack cancer. Basically, it's a strategy that helps the immune system attack cancer cells.

This trial, conducted at the Memorial Sloan Kettering Cancer Center in New York, focused on patients with cancers that normally respond well to immunotherapy treatments, which comprise 2 to 3 percent of patients with cancerous tumors. The novelty is that only immunotherapy was used, without chemotherapy or surgery, using a drug called dostarlimab.

Of the 103 patients in this trial, 98 were completely cured with the first treatment. Of the 5 cases in which the cancer returned, 4 were completely cured with additional doses of immunotherapy, while in the 5th case, the tumor shrank but did not disappear."

Comment Re:You know what... (Score 1) 375

A very strict indicator that correlates with quality of healthcare is life expectancy, and according to Our World in Data , the US performance is very bad.

As you can see in the kinked chart, US life expectancy is 79.3 years for a per-capita health expenditure of $ 10,827 (PPP based on 2015 prices). Chile, for example, has a life expectancy of 81.17 years, spending $ 2,453 per capita. That's less than 23% compared to the US.

Submission + - Ask Slashdot: Printer recommendation for family with kids in elementary school? 3

Submitted by jalvarez13
jalvarez13 writes: My venerable HP Officejet Pro 8600 Plus is showing its age and it has become expensive to operate due to the cost of the original cartridges. I tried some alternative cartidges but the printer rejects them.

Now that schools still require kids to print stuf at home (mine are in 2nd and 4th grade), and my wife also needs to use the priner, I think it may be wise to invest in a good quality printer that has a lower cost per page (maybe laser?).

I that context, I'd love to have unbiased information about brand quality, printing technology, cost efficiency, and other factors that I might have missed. Any thoughts?

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