My prediction is that in the not to distant future solar/wind + storage will be able to replace nuclear in most areas on Earth. The growth of solar has historically been underestimated [1], and it will continue to be underestimated. Even if nuclear gets cheaper, solar will get cheaper faster.
The development of storage has a long way to go. Outside batteries, there are other options, such as pumped storage. Even then, battery prices might go down enough to make other forms of storage uneconomic.
I also predict that a revolution is yet to happen in the transport of energy. For those areas that can't be self-sufficient in solar/wind, it may turn out to be cheaper to capture renewable energy elsewhere then transport it to where it needs to be used (we already do that with fossil fuels).
I got 97/100 (80.5k) by picking the answer that has no relation to the word. Most of the incorrect answers bore some relation to the word, whether that be phonetic or a similarity to a root word.
Yeah I got 75k~ and did something similar ... most of the expert and grandmaster ones had at least 1 or 2 obvious incorrect answers, then it was a 50/50 so I usually went for the thing that sounded either closer to the root of the word or completely left-field
Not quite an arbitrary Personal Locator Beacon, but it can help rescuers home in from a distance. It's cheap because the tag is just an antenna and a diode.
As someone in the medical imaging field, are you aware of anyone working on passive sonar for medical imaging? I'm curious, as it's something that I've always thought would be fun to work on.
For context I'm in engineering consultancy, so by no means an expert but I probably have enough experience to be on the other side of the Kruger curve dip.
Passive sonar in the naval sense means listening only, not emitting. Do you mean imaging that relies solely on acoustic energy already present and emitted by the body? If so, then generally no. You have two types of "passive" imaging. First would be hardware-passive, as in MR elastography (most common), where the patient wears a transducer pad, and vibration is actively generated by a driver. You've then got algorithmically-passive, which is more analogue to passive sonar, reconstructing tissue stiffness from ambient broadband vibration without the emitted probing pulse, but that is very much entirely academic. I guess the question would be, why is it worth pursuing when you have something like optical coherence elastography (OCE) for non-invasive profiling. Doing it using noisy ultrasound method becomes redundant. There are other methods, but the outcome is the same.
Generally (this is true for all systems, not just humans) you need to induce energy into it to more effectively measure it's output. Think of it like a bell - if I want to hear the note it produces, it's much easier to hear what this is if I ring it with a hammer. Granted, it will be "passively" resonating to a point where, with a sensitive enough sensor, I could probably pick up the output without the hammer - but that is a pointless problem to solve. I could hit a bell with a soft hammer a million times over without causing damage to it. The lifetime of the person hitting it with a hammer is far shorter than the accumulative damage to the bell before it breaks. The same is true for humans. You could effectively run a very low-energy, 60Hz vibration through a person (which is how the pads work) for multiple lifetimes before it would cause significant damage, so there comes little point in solving that problem. As such, true "passive" imaging is functionally pointless if your outcome is "safely image a patient". You're overengineering your solution to solve a problem that is only relevant if your patient was planning on living for 1000+ years.
I'm thinking passive, as in using only acoustic energy that is already present. Partly it's about minimising irradiation, which you are saying is not a concern.
The more interesting aspect to me is whether the ambient emissions carry useful information. I recall a paper from a few years ago about yeast emitting sounds (mechanical vibrations) in the kHz range. I guess the question I am interested in is "what does life sound like at the cellular level?" Maybe it is silent, but my gut says it's probably making some sound, even if it's very weak. The questions are then along the lines of "What does a healthy cell sound like?", "Do different cells make different sounds?", "Do sick cells make different sounds to healthy cells?". It's absolute pie-in-the-sky stuff, but it would be fascinating to know.
My background is radio communications (with some acoustics) and radio comms has a history of things that used to be considered random noise turning out to be useful signal as processing has developed to the point where signals can be resolved. For example, multipath reflections used to be considered just random interference until the invention of MIMO, at which point they became useful signals and comms systems took a leap forward.
Likely the continued existence of taxis are keeping Uber's prices in check in the Australian market.
Uber will be running an optimisation model and be charging the maximum market can sustain, with additional goals such as eliminating competition and not being shut down by regulators.
It's worth noting that most communications specifications that involve an encoder/decoder pair communicating over a channel only specify the encoder. Standards purposely leave the decoder open to allow systems to progress as technology develops and to allow competition between implementations. This also makes a standard simpler, as a decoder is usually more complex than an encoder since it has to deal with noise and other effects introduced by the channel. Consequently, implementing a competitive standards compliant decoder involves R&D and is not a case of following a predefined path.
I've always seen Bellard as an engineer who programs rather than a pure programmer.
The concept is similar, in that with MPEG it is the encoder that is the harder of the two, since it has to deal with the noise and real-world effects in the source image.
What I should have written is that the "hard" part, which is generally left unspecified, is the part that removes redundancy. An MPEG encoder removes redundancy whilst its decoder adds redundancy. An FEC/communications encoder adds redundancy whilst its decoder removes redundancy.
It's not really about difficulty (although encoding is definitely far more difficult), it's about there being multiple valid encodings.
If you have two red boxes on a black background in one frame, and a single red box in the middle on the next, UIUI there are at least two ways to encode this: "left box moved right a bit; right box disappears" and "right box mounts left a bit; let box disappears".
In a complex scene, there is a huge space of possible ways to encode a frame that give identical outputs, and even more that are lossy. Choosing one that compresses well but is visually similar (and not too slow to find) is a quality issue for the codec. It wouldn't make sense to specify the algorithm for that in the spec.
I agree. We are in danger of arguing about semantics/language, despite the effects of the words we are using being the same. I guess that's why Information Theorists use mathematics over words.
The format for all modern video codecs is not the kind of format where any specific piece of uncompressed input should always be encoded the same way, but more like a very restricted programming language that gives the encoder a lot of tools to compress the video, and which tools they use and how they use them are up to them.
I think it's neither the encoder nor the decoder that's specified but rather the encoding ie the bitstream format. At least for video streams building a competitive encoder is far more difficult than the corresponding decoder.
Careful using body-worn devices when plugged in. Medical power supplies have special requirements to avoid electrocution, because they are often powering equipment in contact with a person's body. Consumer power supplies probably don't, on the assumption that the device will not be charging whilst being worn.
People have died from using headphones plugged into USB chargers.
At least here in the EU they do and i think it's the case in most countries world wide?
Looks like that 2014 case might have been a sub-standard charger that didn't conform to required safety standards?
I actually experienced a (cheap) charger exploding under my desk back around 2015.
There's a youtuber called BigClive that delights in tearing down the bad chargers. Ken Shirrif's blog is the best resource i know of for this topic though.
Anyway, i feel pretty safe with the vision pro plugged in with an apple charger. The battery does get warm though...
In that case it was a cheap USB supply, though there are other reports of similar. "Good" consumer power supply are designed to IEC standards, but to keep the cost down they are different standards to those used for wearable medical equipment. Medical equipment has to conform to IEC 60601, which governs things like electrical isolation and safe failure modes.
> i feel pretty safe
So be it. It is unlikely, but even a good power supply can fail in the face of a voltage surge on the mains. Absolutely don't wear it plugged in if there is any hint of a thunderstorm!
The electricity infrastructure where I was live was owned by the government. It's only in the last 15 years it was sold off to private interests [1]. I suspect you will find that the electricity systems in many regions are still government owned.
Should be noted that Australia, and even NSW, had quite a few different systems. Country NSW was largely done by the (local) county councils and they didn’t seek to profit by once the debt was cleared and instead wanted to give out cheap power until they had to take on more debt.
This was deeply offensive to the economists of the 80s and 90s and so they were taken over by the state government and turned into a for profit company.
It was corporatised before it was sold off. Privatisation of the NSW energy market began about 30 years ago at this point.
I'd keep the Moonraker film in mind as a metric for self sustaining colonies created by billionaires. They can't be trusted unless they are also working to fix what we already have.
Paper: https://www.medrxiv.org/content/10.1101/2025.05.19.25327921v...
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