I had a similar experience recently, the dental assistant told me "we're going to do your x-rays now, but the controller isn't working right so I have to use a workaround, it'll take a little longer." I told her to stop what she was doing, there would be no x-rays for me, and explained why. I'm 99.99% certain I would have been fine, but the Therac-25 story is so horrifying, I decided to give in to my irrational fear.
I am a medical physicist. The Therac-25 disaster is retold and explained to every student of medical physics, of course. So I'm happy to inform you that it is not physically possible for the kind of error that occurred with the Therac-25 to occur with a diagnostic X-ray system.
You see, there are basically two kinds of X-ray machines used in medicine. One is just a standard cathode-ray tube (in fact, CRT televisions are basically the same design and both fall under 21 CFR 1020): a very high voltage is produced between a hot filament cathode and a tungsten anode, and electrons leave the cathode [1] and fly towards the anode where they produce X-rays. Because the energy that accelerates the electrons is entirely contained in the electric field between the cathode and the anode, the electrons cannot reach the required kinetic energy without moving towards the anode. All diagnostic X-ray imaging equipment is basically of this form, although there are a few unreliable machines that come with fancy sales pitches where the hot filament is replaced by some carbon nanotube thing. Nobody recommends these, but they aren't dangerous either.
The other kind of X-ray generator is an accelerator. Here there is also a cathode and an anode, but in between there are additional electric fields which take the form of standing radio waves. The released electrons are synchronized with the radio waves so that they gain far more kinetic energy from the oscillating fields than they do from the static field between the anode and the cathode.
In an accelerator, it is possible for the electrons to fly past the anode and hit the patient directly. This is what happened with the Therac-25. Only about one percent of the electron energy is converted into useful X-rays when fast-moving electrons strike a piece of tungsten (or any other material; tungsten is the most durable).
In some cases, you actually want the electrons to hit the patient. This is called "electron-beam therapy" and it is used to treat skin cancers and other shallow tumors because electrons do not penetrate as deeply as X-rays. In order to do this safely, the electron beam intensity is reduced dramatically, to about 1% (of course) of the "tube current" used to generate X-rays.
You may have already guessed the problem. In the Therac-25, it was possible for the electron beam to be configured at an X-ray intensity while the beam-directing magnets (we say "bending magnets") were aiming it at the patient. This causes a lethal overdose of radiation — a hundred times too much.
However, a diagnostic X-ray tube does not have any magnets directing the beam, nor does it have any standing radio waves ("RF oscillators") accelerating the electrons enough to escape the potential well created by the anode. These machines cannot produce electron beams outside the tube because the electrons are simply "falling" into the anode and there is nothing to "push" them away. It would be a little bit like dropping a rock down a well and seeing it fly back up into the sky.
On the other hand, dental x-rays are overused and do not improve dentists' ability to detect cavities in most patient populations.
And even though a diagnostic x-ray machine can't point an electron beam at you, it can still give you a bigger than intended dose. (Yes, I know that dental x-ray doses are typically very low to start with).
US social media companies have been banned in China for many years, so in fact the “brainwashing” you’re referring to has only gone in one direction until now.
You raise an important point. Why should a Chinese company be allowed to operate freely in the U.S. when U.S. companies offering similar services are totally banned in China? Doesn’t this violate the principles of free trade and frameworks to which the two countries have agreed?
I’m not concerned so much about TikTok as spyware or data gathering or a vector for influencing young minds… though it is all of that, to some extent.
The real problem is the one sided nature of the U.S.-China trade relationship.
I do think that the TikTok ban is being taken too lightly by the people of US. But the more interesting point is that your logic implies that China making a sensible move in banning US companies. There is a real question of why companies like Google are allowed to operate outside the US - if it is this big a deal to the US politicians it suggests their military has been using it aggressively against opponents with some success.
"Why would an adult not hit someone when that someone hits them?"
Some people believe that not retaliating stops cycles and systems. Some of us have principles beyond the very childlike, "well, they did it first".
If you believe state censorship is bad, you should oppose it when it is deployed, even if it's deployed against someone you think is also bad.
Like, I think using slurs is bad. I oppose using slurs, even against people I loathe. I have a principal, and I do not violate that principle even if it would hurt people I would consider my opponents.
Same here. My commitment to my principal that "state censorship is bad" far outweighs any feelings about China.
Sure; but negotiations involve a give and take. You can't push things in the a direction if you just tout your purity and one side gives in and gets rolled over.
I think some progress was made getting TikTok on US servers and the US hires etc. Maybe more transparency in how the company operated or observers within could have been good next steps. Maybe some mutual concession with some version of US media operating within China.
Ideally finding benefit to nation states competition benefits global citizens in some way such as the green race transition to renewables is good ... Can we have privacy and democratic media race somehow? ... Maybe not possible :)
Stiff systems like whatever version of Communism the Chinese have now, with Emperor for Life Xi don't do as well with changing circumstances and the buildup their own internal contradictions as well as the flexible democracies so there is more than just China's demographic collapse in the equation.
Good point but it remains to be seen. China has seemed to look at the Soviets and 'improved' upon their design. At the same time the West has dove deeper into their downsides (corruption) with no improvement in sight. Does China really need to last forever or do they just need to outlast their rival?
Similarly, I’ve had to privately advise coworkers not to use the term “let a thousand flowers bloom” as an idiom meaning “let’s get ideas from lots of people.” It sounds great until you understand the horrible historical context in which it was originally said.
I think things like this are a type of resource exhaustion attack on society. No one can be aware of all things potentially offensive to someone else. Its the hyperaware judges excluding mens rea from the equation before deciding guilt. What is the harm done to someone who might find this offensive? Why spend your time lifting the veil and shaming those around you who have no intention of harming anyone with their language? If they happen to offend a party some day, I am sure they will adjust their vocabulary accordingly. Why the haste to preempt this rare event?
Because a number of people on our team were born and raised in China. It’s very likely that some of them had family affected by the awful aftermath of the Hundred Flowers campaign.
Huh. What do you mean? Why should the phrase not be used?
My only experience with the phrase is to mean something along the lines of a calculated ploy to lure dissidents into exposing themselves for later punishment. The horrible historical context is pretty much the entire point of making the allusion at all.
I disagree. The usage has detached from the historical context of the original (mis)quote, and there’s no good reason for it to be eternally enslaved by it. This is also reflected in entries like [0] and [1]. Indeed, the Wiktionary entry notes that it may “be used ironically, in negative view” of the Hundred Flower Campaign, which in turn means that by default that context isn’t implied, and instead as a proverb it merely has the meaning described above in the entry.
I don’t think it would be acceptable to say “Arbeiten macht frei” in a casual conversation. Just because Chinese history is distant from and unfamiliar to western experience doesn’t mean we should trivialize it.
Thanks, Ondsel - it was a worthy and welcome attempt. And you left FreeCAD much better off than when you found it. For that reason, Ondsel may be shutting down, but it is anything but a failure.
This seems extremely negative on China, and echoes a lot of web content that frankly smacks of anti-Chinese propaganda. To be clear, I'm not accusing you of being a propagandist and in fact I believe you are 100% sincere, and I'm glad you've provided your opinion here. But the similarity of your description to the various China-bashing outlets is striking and makes me question the sources of it.
My opinions are my own, based on decades of experience since first living in China in 2001. I last lived there in 2022. I actually run businesses, and my social networks consist of disparate experiences, which probably means my view of things is more nuanced and rationally founded than fly-in journalists or those watching only the statistics, albeit necessarily only a "partial truth" (nobody knows exactly what is going on across the country, not even the government). Perhaps if you raised concerns regarding a specific point it would be possible to respond more fully.
You clearly have a wealth of expertise that I don't, and because of that, I again thank you for your original comment. It's probably better for me to simply consider your point of view rather than try to question it using second-hand data.
And why do you suppose these ostensible 'China bashers' believe what they do? Do you believe that people just wake up one morning and say to themselves: 'I'm going to go online and hate on China today' for absolutely no reason at all?
They're literally inundated with the message in all media. The US government spread rumors about Chinese vaccines it knew to be safe to convince people not to take them. The US has budgeted 1.6 billion dollars for propaganda activity against China.
The coordination and omnipresence of the western media is the most impressive thing I’ve ever experienced. Once you catch them all lying about incontestable truths in unison, the charade falls apart.
Americans grow up in this soup. They even have rebellious media companies that say edgy things, but all tow the party line. It’s genuinely incredible.
It happens all the time and it would be quite a bit of work to prepare a list to the level of un-disputability on my part (which seems to be required as Hacker News is feeling very pro-establishment at the moment), but a recent example of this is the failure of the Iron Dome system against Iranian rockets.
Videos online very, very clearly showed many rockets bypassing the system, with some interceptions in the video that made it all the more obvious how many rockets were not being intercepted. All western media claimed the Iron Dome was exceedingly successful and blocked 90%+ of the missiles. This was also not corroborated by non-western sources. It wasn't until Planet Labs released evidence of dozens of strikes on an airbase that this specific messaging decreased.
At that point, they didn't acknowledge that 'error', but instead shifted the narrative to say that the attack, which Iran gave several hours warning of and had explicitly designed not to take lives, had failed because nobody got killed.
Israel coverage in general is a great topic to witness this phenomenon.
That's not nearly the impression that I got from reading the GP comment. Did you mean to reply to a different one?
If anything, it seemed rosy; for example I was under the impression that China had cracked down on VPNs. But if GP says they're still widely accessible, then it leaves me with the impression that China has more free access to information than I previously thought.
It strikes me as a picture filled with both positives and negatives, and the point being made is not that China is a doomed sinking ship, but that the challenges it is dealing with aren't analogous to the ones faced by the US in the 19th century. (I don't know if wealthy 19th-century Americans did or did not aspire to move their wealth to Europe or send their kids abroad for school, but at least, the argument being made by the poster suggests a belief that they were not).
China has much more freedom than I was led to believe growing up. The restrictions seem pretty neatly constrained to things that are genuinely threats to public safety, “social harmony”, or national security.
It seems scary until you think about the kind of information warfare that a certain cross pacific neighbor likes to employ, frequently.
Please tell me you're kidding. There is way, way more pro-Chinese propaganda online than anti-Chinese. So overt at this point that you'd have to be willfully blind not to notice.
Either do I, as I was born a few decades too late for that. But there is a lot on Reddit and other popular forums. And on HN, even in this very discussion.
Human speech is 54 bits per second (and that is surprisingly uniform across languages). Bandwidth from a consumer-grade EEG headband is maybe four bits per second. Something doesn't add up.
I agree about the EEG part. I was curious how they managed to get that work, and found [0], which seem to confirm my guess: they didn't - they went for EMG instead. Now EMG sounds very plausible, given that it's well-understood, already applied for "controlling with thought" (prosthetics), and a person can learn to make their signal more clear/intentional, easier for the machine to understand.
As for 54 bits per second[1], that's assuming healthy person speaking, which is not relevant here. Communication systems for people unable to talk, write or sign because of ALS, paralysis, or similar things, do not have to aim for 54 bits per second! A few bits per second is already great! The alternative is no communication, or like half a bit per second but only when you're paying very close attention.
Here are some quotes from [0] about the most important aspects of the solution:
> “The LLM expands what you’re saying. And then I confirm before sending it back. So there’s an interaction with the LLM where I build what I want it to say, and then I get to approve the final message,” explained Pedro. (...) “The LLM that takes a basic prompt and expands it into a fully fledged answer, almost right away. I wouldn’t have time to type all of that in the natural way. So I’m using the LLM to do the heavy lifting on the response,” he added.
> He also pointed out that the wearer has absolute control of what they are outputting: “It’s not recording what I’m thinking. It’s recording what I want to say. So it’s like having a conversation.
So no magic here. Seems like a direct combination of:
1. Using EMG as input to get specific words/phrases;
2. Using LLM to expand those into full-blown sentences;
3. Using a TTS model to sound it out in a person's voice.
Feels like 2 and 3 could be applied to existing solutions across various ranges of illness and disabilities.
Thanks for the reference, I suspected it would be EMG as well. Especially in the video you can see how the patient modulates his eyebrow, facial muscles, and mouth. The vestigial muscle movements can be decoded to speech with the help of LLM much more easily. Actually, if form factor was not a concern, this can be done even more easily with other sensors as well.
This is great, thanks for creating this. I hope it brings you success, I certainly plan on using it.
One important aspect of choosing a protein powder is the amino balance - especially for vegan proteins. Unfortunately many brands don’t provide this info, and you have to infer it from the ingredients.
An unprecedented peek-behind-the-covers at the inside of mainstream media brain.
Man with wide eyes and stock photos and nordvpn sponsorship on set with full makeup and steampunk costume rambles through various headlines, not forgetting to show you how to (mis)interpret facts, and how to manifest life as a rabid political fanatic, ready to ruin any dialog you come across with barking and screeching and red eyes.
There is nothing in that video that even resembles thought or rationality, it is just classic mainstream media non-sequitur that adorns the regalia of knowledge and batters the viewer with meaningless "facts" and "figures" until they are in a state of ready-to-be-filled aporia.
It's not about "intelligence" or about any particular factual misinterpretation, I'm sure there's some "source" that more-or-less backs each individual claim made in the video, the problem is, in broad strokes, the standard of evidence for each individual "fact", and the narrative that guides the viewer through the set of curated and disconnected facts to an implied conclusion, which is less like a conclusion and more like a sentiment: "The crypto industry is a bunch of rich scammers like FTX and Sam Bankman Fried that are trying to grease the wheels of power with all of their ill-gotten wealth to protect themselves and continue to rob dopes that are buying into this trash." It's easy to imagine a conjugate set of disconnected and non-sequitur facts that with the right presentation lead to precisely the opposite conclusion.
But, neither of those is thinking. I mean that, the problem is not that the ambiguity of the situation provides for two or more interpretations, which it seems to me that it does, but that this mode of investigation, which outwardly accounts for itself like "Each side go to your corner and gather as many facts as you can, then we'll gather in the middle and compare, whoever has the more and heavier facts shall be found truthful!", but is really more like, "Let's all divide ourselves in two, randomly, and amass as many facts as we can that back up our point-of-view, while dismissing any that support the other, and just for fun let's add in hating the other corner too, because it makes all of this more exciting."
If you hang your thinking on the results of some surveys, and one account of what happened in some particular historical event, plus some truistic phrase like "All's well that end's well" and a couple of well-timed stock photo gags to pull it all together, you will find yourself 1. impermeable to any ideas that don't fit in the point-of-view or framing of the question you already have and 2. completely and willfully uncurious about the world and questions you aren't already asking about the things you don't already have preconceived notions of.
Regular subscribers to Patrick Boyle know that his channel is not really about finance - and certainly not about crypto. Most of the time, the channel is meant to be a place to talk about rap music. It's very subtle.
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